Our readers keep the lights on and my morning glass full of iced black tea. As an Amazon Associate, I earn from qualifying purchases.11 Best 1.6 GPF Toilet | Four-Inch Valve Ends Clog Calls

Specs are compiled from manufacturer listings and verified buyer reviews and can change over time — please confirm the key details on the product page before buying.

The short answer: the HOROW T0338W is the easiest buy of the bunch — a full-size elongated bowl in a 26.6-inch-deep body that fits a small bathroom. Searching for the best 1.6 gpf toilet really means hunting one number: 1.6 gallons per flush. That figure is the full-flush setting the U.S. government caps standard residential toilets at, and it is the line between a toilet that still clears the bowl in one go and one you end up flushing twice.

I’m Mohammad Maruf — the founder and writer behind KitchPrep. This guide is built by comparing the manufacturers’ published specifications and the patterns across verified customer reviews, so you get each pick’s real strengths and trade-offs instead of marketing spin.

Every toilet below delivers a true 1.6 GPF full flush (1.6 gallons per flush — the low-consumption standard), and each one is sorted by what it does best. The lineup runs from compact ADA-height one-pieces (ADA height means the seat sits higher, so sitting down and standing up takes less effort) to pressure-assisted and basement-pump models, so you can match one to your exact bathroom before you buy.

Our Picks at a Glance

HOROW T0338W One Piece Toilet with ADA Chair Height 17.3', Dual Flush
Best OverallHOROW T0338W One Piece Toilet with ADA Chair Height 17.3″, Dual Flush4.5★989 ratingsThe small-bathroom pick that still seats you at a comfortable 17.3 inches. The HOROW T0338W tops this list because it fits a small room without giving up comfort.Check Price on Amazon
Elongated One Piece Toilet with 17.3' ADA Comfort Chair Height Seat, OT-001
Top PerformerElongated One Piece Toilet with 17.3″ ADA Comfort Chair Height Seat, OT-0014.5★62 ratingsA taller, deeper bowl that leans on a 1000g MaP score to clear in one press. If bowl-clearing power is your whole reason for shopping, this is the one to study.Check Price on Amazon
VEVOR One-Piece Toilet, Elongated Vortex Dual-Flush 1.1/1.6 GPF
Compact PickVEVOR One-Piece Toilet, Elongated Vortex Dual-Flush 1.1/1.6 GPF4.9★29 ratingsThe narrow-bathroom answer that ships on a 10-inch rough-in instead of the usual 12. Most toilets here want a 12-inch rough-in — the gap from the back wall to the floor drain bolts.Check Price on Amazon

How To Choose The Best 1.6 GPF Toilet

A toilet lasts twenty years, and four specs decide whether the one you order fits your floor and clears your bowl.

Start With Rough-In, Or Nothing Else Matters

Measure one thing before you buy: the rough-in, which is the distance from the finished back wall to the center of the floor drain bolts. Most homes use a 12-inch rough-in, but a 10-inch version exists, and the VEVOR in this list ships in a 10-inch size. A 12-inch toilet cannot be forced onto a 10-inch floor, so check your measurement first.

Understand What 1.6 GPF Actually Means

GPF stands for gallons per flush. The 1.6 GPF figure is the full-flush volume that meets federal standards on modern toilets, and a dual-flush unit pairs it with a lighter 1.1 GPF press for liquid waste. The lighter press saves water on the easy trips; the 1.6 side does the heavy lifting.

MaP Score: The Bowl-Clearing Number

MaP is a third-party test that rates how much waste a toilet clears in a single flush, measured in grams. A 1000g MaP score is the practical benchmark — it tells you the bowl empties on one press instead of two or three.

Comfort Height vs Standard Height

Comfort height is around 17 inches from floor to seat rim — a chair-height toilet that lets you sit down and stand up with less effort. Standard height is generally 15 to 17 inches. Taller family members and anyone with knee concerns tend to prefer the 17-inch versions; smaller users sometimes find them a touch high.

Quick Comparison

Model Best For Flush Rating Seat Height Rough-In Amazon
HOROW T0338W★ Best Overall Small bathrooms with ADA needs 1.1 / 1.6 GPF 17.3″ 10″ or 12″ Amazon
AKNIRL OT-001Top Performer Biggest bowl-clearing score 1.0 / 1.6 GPF 17.3″ 12″ Amazon
VEVOR W2121-10″Compact Pick Narrow bathrooms on 10″ plumbing 1.1 / 1.6 GPF 16″ 10″ Amazon
Abruzzo AB-23T01-MB Matte black statement looks 1.1 / 1.6 GPF 17″ 12″ Amazon
Swiss Madison Ivy Glossy black with hidden plumbing 1.1 / 1.6 GPF 15-17″ 12″ Amazon
Swiss Madison Chateau Low-profile under a shelf 1.1 / 1.6 GPF 15-17″ 12″ Amazon
TOTO Drake CST776CSFG#01 Rimless bowl that stays clean 1.6 GPF Universal Height 12″ Amazon
American Standard Cadet Clog-prone households 1.6 GPF Chair Height 12″ Amazon
Kohler Highline Classic Self-swooshing bowl cleaning 1.6 GPF Comfort Height 12″ Amazon
Simple Project MT-1-400B Basements with no drain below 1.6 GPF Standard Upflush system Amazon
American Standard Champion 4 Heavy-duty flushing in one unit 1.6 GPF 16.5″ 12″ Amazon

In‑Depth Reviews

★ Best Overall

1. HOROW T0338W One Piece Toilet with ADA Chair Height 17.3″, Dual Flush

Our pick — 4.5★ from 950+ verified ratings; the strongest balance of quality and price.

Compact One-Piece17.3″ ADA Height

The small-bathroom pick that still seats you at a comfortable 17.3 inches.

The HOROW T0338W tops this list because it fits a small room without giving up comfort. It packs a full elongated bowl into a body just 26.6 inches deep, 15 inches wide and 26 inches tall, so it tucks into a powder room or a tight guest bath. The seat sits at a 17.3-inch ADA chair height, so you sit down and stand up with far less effort than a low standard-height bowl demands.

Under the lid, the flush is a dual-flush setup rated 1.1/1.6 GPF, backed by a 1000g MaP score. MaP is a third-party test of how much waste clears in a single press. A 1000g result means the bowl empties in one flush instead of the double-press you get from a weak low-flow model. Buyers echo that — the flush is the second-most praised trait after build quality, and it cleans the whole bowl in one go.

The one-piece body has no gap between tank and base, so there is no crevice to scrub around. The soft-close seat lowers without a slam, and the screw-fixed elongated seat never shifts. Buyers report assembling it solo plus one helper to lift it onto the floor bolts, and it arrives with everything except the wax ring already in the box.

Why It Takes First Place

  • Compact 26.6″D footprint fits tight bathrooms
  • 17.3″ ADA chair-height seat for easier standing
  • 1.1/1.6 GPF dual flush with a 1000g MaP score
  • Soft-close seat and smooth one-piece exterior

The Honest Trade-Off

  • 99.2 pounds makes it a two-person lift onto the bolts
  • Side access holes are snug, so tightening the floor nuts takes patience

Grab this one: if your bathroom is tight but you still want a comfortable chair-height seat and a one-flush bowl.

Skip it: if you need plumbing on the other side of the wall — check the rough-in before you buy.

Top Performer

2. Elongated One Piece Toilet with 17.3″ ADA Comfort Chair Height Seat, OT-001

1000g MaP ScoreWaterSense Certified

A taller, deeper bowl that leans on a 1000g MaP score to clear in one press.

If bowl-clearing power is your whole reason for shopping, this is the one to study. The AKNIRL OT-001 runs a dual-flush 1.0/1.6 GPF system with a 1000g MaP score and a siphon jet — the internal jet that pushes waste out of the bowl rather than letting gravity do all the work. In plain terms, that combination is built to clear the bowl in a single flush, which is why buyers keep calling out a strong flush as the standout trait.

It is also one of the taller picks here, at 17.3 inches of ADA comfort chair height, and the elongated bowl adds room. That extra height and depth is the trade-off to know about: the body measures 28.5 inches deep by 14.25 inches wide by 29.25 inches tall, so it eats more floor than the HOROW. In a genuinely tiny powder room, that extra footprint can be the deciding factor.

Owners mention the install went smoothly and that it fits a 12-inch rough-in perfectly, with no leaks once sealed. The smooth one-piece body wipes down quickly, and a fully glazed trapway — the internal passage waste travels through — helps keep the bowl cleaner between scrubs. One recurring note: the difference between the light and full flush press is not very noticeable, so it behaves more like a single powerful flush.

What Buyers Notice: quality and appearance are the two most-praised traits, and value for money comes right behind them. The 1000g MaP score and dual-flush 1.0/1.6 GPF setup are the specs that earn that praise.

The Fine Print: it carries WaterSense, DOE, cUPC and CEC certification, which speaks to its water-saving build — but the deep 28.5-inch body needs more floor space than a compact one-piece.

Reach for this if… you have the floor space and want the biggest bowl-clearing score on the mid-range shelf.

Look elsewhere if… your bathroom is a true powder-room shoebox — the deeper body may not fit.

Compact Pick

3. VEVOR One-Piece Toilet, Elongated Vortex Dual-Flush 1.1/1.6 GPF

10″ Rough-InVortex Dual-Flush

The narrow-bathroom answer that ships on a 10-inch rough-in instead of the usual 12.

Most toilets here want a 12-inch rough-in — the gap from the back wall to the floor drain bolts. The VEVOR W2121-10″ is built for a 10-inch rough-in instead, which matters if your older home was plumbed that way. Force a 12-inch toilet onto a 10-inch floor and it simply will not sit against the wall, so this is the spec that decides the purchase.

This is the most compact body on the list at 26.55 inches deep by 14.96 inches wide by 27.36 inches tall, so it fits narrow layouts without crowding you. The smooth one-piece body means no gap between tank and base to collect grime. The dual flush runs 1.1/1.6 GPF — a lighter press on the left for liquid waste and a stronger rinse on the right.

The seat sits at a 16-inch ergonomic height, which is lower than a 17.3-inch comfort-height model. That is the trade-off: taller household members often prefer the extra inch of a chair-height bowl, while shorter users and some seniors find a 16-inch seat easier to reach. The high-temperature-fired glaze resists dirt buildup, so the surface stays cleaner between scrubs.

Where It Fits Best: a narrow bathroom or an older home plumbed for a 10-inch rough-in, where most 12-inch toilets simply will not go.

Keep In Mind: at 16 inches the seat sits below the 17.3-inch comfort-height picks, so measure the height you actually want before committing.

The call: buy it for the 10-inch rough-in and the slimmest body on this list — 14.96 inches wide it slips into the tightest footprint.

Think twice: if you set your heart on a 17-inch chair height, this 16-inch seat will feel low.

Bold Design

4. Abruzzo Modern One Piece Toilet, Elongated Dual Flush, Matte Black

Matte Black Finish17″ Comfort Height

The black statement piece that still nails the flush numbers everyone actually needs.

The Abruzzo AB-23T01-MB in matte black is the pick when your remodel needs a focal point. The elongated bowl gives you room and comfort, and the smooth one-piece body eliminates the crevices where grime collects, so a quick wipe keeps the smooth surface looking new. Buyers describe it exactly as expected and easy to install — one summed up the look simply: black is the new white.

The specs behind the looks are solid: dual flush at 1.1/1.6 GPF, a 17-inch comfort height for easier sitting and standing, and a soft-close polypropylene seat with a quick-release hinge so you can pull it off for a full clean. The system is designed for a 12-inch standard rough-in and ships with the wax ring, floor bolts and hardware in the box, so most homeowners can finish the job with basic tools.

One note worth sizing honestly: an occasional unit has arrived broken in transit — a shipping risk with any ceramic toilet that weighs 106 pounds, not a design fault. The matte black finish also shows water spots more readily than white, so it rewards a quick wipe-down routine. Buyers mostly report the finish arriving as expected and installing with no fuss.

Strengths That Show

  • Matte black finish that turns the toilet into a design feature
  • 17-inch comfort height eases sitting and standing
  • 1.1/1.6 GPF dual flush keeps water use efficient
  • Everything for a DIY install comes in the box except a good seal

Heads-Up Before You Buy

  • At 106 pounds it is a two-person lift onto the bolts
  • Matte black shows water spots faster than a white bowl

Perfect for: a black-and-chrome bathroom remodel where the toilet is meant to be seen.

Pass on it: if you want a low-maintenance bowl that hides every watermark — glossy white still wins that job.

Showstopper Look

5. Ivy One Piece Toilet Dual Vortex Flush in Glossy Black 1.1/1.6 GPF

Glossy BlackSkirted Trapway

A glossy black one-piece whose hidden plumbing keeps the lines clean and easy to wipe.

Owners rave about the look first: a glossy black ceramic body with a skirted trapway that hides the plumbing behind a smooth panel. That skirted design means there is no pipe bulge to clean around, just a flat surface you wipe down in seconds. The ceramic itself is scratch-resistant and non-porous, so it holds its finish through daily use.

The bowl is a standard elongated shape for extra room, and the dual flush gives you a 1.1 GPF light press or a 1.6 GPF full press. The fully glazed trapway — the internal waste passage — keeps water moving freely and helps fend off clogs. It is built for a standard 12-inch rough-in with 3-inch access holes for the floor bolts. At 94.9 pounds it is one of the lighter one-pieces to wrestle into place, though a second set of hands still helps.

The honest caveats: the finish can show smudges where glossy black meets hard water, and a few units have arrived with a small tank-to-bowl issue, so inspect the porcelain on delivery. One buyer even reported swapping in a 10-inch rough-in version to suit a smaller base — proof the compact body adapts, as long as you know your measurement. Overall it is the pick for a modern, dramatic bathroom.

What Buyers Love: the appearance and the build quality, in that order — the glossy black finish and skirted body are the reasons most buyers chose it.

The Realistic Catch: glossy black shows hard-water spots, and it can be tough solo — the hidden floor screws are fiddly to align.

Buy it if… your bathroom leans modern and you want the plumbing to disappear into one clean black form.

Not for you if… you would rather a bowl that hides hard-water marks — go white for that.

Sleek Value

6. Chateau One-Piece Elongated Toilet Dual-Flush in Glossy Black 1.1/1.6 GPF

Low-Profile TankGlossy Black

A short, low tank that slips under a window or shelf when a tall toilet will not.

The Chateau stands out for a shape most toilets do not offer: it is only 24 inches tall, so it fits beneath a windowsill or a capped ledge where a full-height tank would collide. That low profile is the whole reason to pick it — for a bath with a low shelf or a tight water closet, it is often the only one that clears.

The rest of the spec sheet is standard: a one-piece elongated body, a 1.1/1.6 GPF dual flush, and a non-porous scratch-resistant ceramic finish. It is built for a 12-inch rough-in and weighs 88 pounds, the lightest floor-mounted unit here, which makes the physical part of installation a touch friendlier for two people. The glazed trapway helps keep water flowing and reduces clog buildup over time.

Keep an eye on the flush power, though — the low tank height can mean less water pressure behind the flush, and some buyers find the dual flush needs a second press for larger loads. A handful of units have arrived with minor glazing or chipping, so inspect the porcelain when it lands.

The Case For It: at just 24 inches tall it solves a specific layout problem no standard toilet can, while still delivering the 1.1/1.6 GPF dual flush and one-piece elongated bowl.

Know Before You Buy: the short tank can weaken flush force, and a few shipments have shown minor glaze blemishes — check the bowl on arrival.

Made for: a bathroom with a shelf or windowsill that forces a low-profile tank.

skip it if… you have the vertical room and want maximum flush force — a taller tank generally pushes harder.

Best Flush Tech

7. TOTO Drake Two-Piece Elongated 1.6 GPF Universal Height TORNADO FLUSH Toilet

TORNADO FLUSHCEFIONTECT Glaze

The rimless bowl with a swirl-flush that scrubs itself while it empties.

This is the toilet for anyone who is tired of scrubbing the inside of the bowl. The TOTO Drake uses TORNADO FLUSH, which swirls water in a circular pattern to wash the full bowl surface with every press — no rim for waste to hide under. On top of that, CEFIONTECT is an ultra-smooth glaze that keeps waste from sticking in the first place, so it washes away easily on the next flush.

It pairs that cleaning tech with a 1.6 GPF single flush, a wide 3-inch flush valve and a siphon jet bowl, all tuned to get the job done in one press. The bowl is a 2-1/8-inch trap seal with a minimum flowing water pressure of 8 psi. TOTO’s Universal Height is taller than a standard toilet and can meet the ADA height requirement, which helps when sitting down and standing up is a consideration. It fits a 12-inch rough-in with a left-hand trip lever.

Bowl-clearing is the headline: customers note it flushes everything in one press, with a second press needed only for excess toilet paper. The recurring gripe is the install, not the performance: it is a two-piece, so the tank bolts on separately, and the tank can need careful tightening. Note that the seat is sold separately, so budget for a TOTO SoftClose seat or a WASHLET bidet seat to finish the look.

Why It Cleans Itself

  • TORNADO FLUSH swirls water around the whole rimless bowl
  • CEFIONTECT glaze stops waste from sticking between flushes
  • Wide 3-inch flush valve and siphon jet clear in one press
  • Universal Height can meet the ADA height requirement

The Cost Of The Tech

  • Seat is sold separately — add it to your plan
  • Two-piece tank install takes patience to seal properly

The verdict: pick it if a self-cleaning bowl and clog-free flushing are worth more to you than a single-piece body.

Worth noting: the rimless design and swirl flush are what you are paying for, so add the seat and a wax ring to your order up front.

Clog Crusher

8. American Standard 2467016.020 Cadet Two-Piece Pressure Assisted Toilet, Chair Height, 1.6 GPF

Pressure-Assisted FlushEverClean Surface

A pressure-assisted flush so forceful it can startle you on the first press.

If your household owns a plunger, the American Standard Cadet is the fix. It uses pressure-assisted siphon jet flush action — compressed air drives the water out with far more force than a standard gravity flush — and it moves 1.6 gallons per flush, which is the low-consumption rating. The EverClean surface works to keep stains from taking hold on the bowl.

Flush power is the whole story here, and buyers confirm it: owners who clogged constantly with their old toilets report going long stretches without ever reaching for a plunger. The bowl sits at chair height with an elongated front for comfort, and the combination bowl-and-tank comes without a seat, so add one to your order. With a limited one-year warranty, it is built to be serviced rather than babied.

Two things to expect. First, pressure-assisted toilets are loud — the flush is an air-and-water whoosh, and buyers call out the noise as the most-mentioned drawback. Second, the tank is heavy and needs a firm two-person lift onto the bowl, and a few owners have needed shims to steady it on uneven floors. Buy a wax-free seal and separate floor bolts, and the install goes far more smoothly.

The Proof In The Flush: flush power is the second-most praised trait, and the pressure-assisted system plus EverClean surface earns it — this is the tool you buy so you stop plunging.

The Price You Pay: that force comes with a noticeably loud flush, and the toilet rocks on an uneven floor unless you shim it — bring a shim kit.

Reach for this if… your old toilet clogs no matter what you do, and you will trade a noisy flush for never owning a plunger again.

Look elsewhere if… the bathroom shares a thin wall with a bedroom — the flush volume is real.

Proven Workhorse

9. Kohler 3493-0 Highline Classic Comfort Height Two-Piece Elongated Chair Height 1.6 GPF Toilet

Comfort HeightSelf-Cleaning Swirl

The name-brand classic that flushes hard and cleans the bowl as it goes.

The Kohler Highline Classic is the one buyers come back to for a second and third bathroom. It runs a powerful 1.6 GPF flush and pairs it with a self-cleaning swirl that washes the bowl as it empties, so maintenance stays minimal. Owners who switched from a weak low-flow toilet report the clogs simply stop. It is a comfort-height chair seat paired with an elongated bowl, so most adults sit down and stand up with less effort.

Where it shines is longevity under real use — buyers describe years of dependable service with no maintenance needed and no power required, which is the appeal of a straightforward gravity toilet done well. The step-by-step instructions make it approachable for a confident DIYer. It shares the comfort-height category with the TOTO Drake, but the Kohler leans on a self-swooshing cleaning action rather than a rimless swirl flush.

The catch is sound and the flush mechanism. Buyers describe a very loud whoosh on flushing, so a thin wall to a bedroom is worth considering. A few units have had the flush lever come loose or the tank arrive needing a factory adjustment — fixable, but a hiccup on the way to a great toilet. The oversized footprint measures 29.5 inches deep by 21.06 inches wide by 31.25 inches tall, so measure your space before buying.

What Earns The Hype: quality and flush power are the two most-praised traits, and buyers who were plagued by clogs say this toilet ends them — the self-cleaning swirl backs that reputation.

Where It Asks Patience: the flush runs loud, and a few units have arrived with the flush lever needing a tweak — worth checking on delivery.

The choice: a long-haul gravity toilet for buyers who value the Kohler name and a bowl that cleans itself with every flush.

The caveat: it is loud and it is big — check both against your bathroom before you commit.

Basement Solution

10. Simple Project Macerating Toilet System with 4-Inlet & 500W Macerator Pump

500W Macerator PumpUpflush 23ft

Adds a real bathroom in a basement where gravity plumbing simply cannot go.

The Simple Project MT-1-400B solves a problem none of the others can. It is a macerating — or upflush — toilet: a 500W motor grinds waste and pumps it up to 23 feet up and away, so you can install a bathroom below the sewer line, in a basement, or anywhere a standard drain cannot reach. It handles 1.6 gallons per flush and adds four water inlets so a sink, shower and washing machine can feed into the same system.

Installation is the reason buyers choose it. Reviewers point out it hooks right into existing plumbing, that set-up took just minutes with the clear instructions, and that it saved them from cutting concrete or paying steep name-brand prices. The soft-closing seat keeps the experience quiet, and the 1280° fired ceramic body with stainless steel components is built to take daily use. A 1-year manufacturer replacement and 2-year repair warranty back it up.

The honest caveat: buyers love the quiet pump and the value, but a few note the flexible rear toilet connector gave trouble and swapped it for a rigid PVC connection — worth planning for. The seat also tends to drift upward on its own, and the instructions are thin enough that a how-to video helps. Measure from toilet to wall carefully before ordering, since the system’s reach depends on your basement’s slope.

Why It Works Where Others Cannot

  • 500W pump lifts waste up to 23 feet up and away
  • Four water inlets let a sink, shower and washer drain in
  • Soft-closing seat keeps it quiet for basement living
  • Installs without cutting concrete to reach a drain

What To Plan Around

  • Rear flexible connector can leak — use rigid PVC instead
  • Instructions are thin; watch a video before you start

Buy it for: finishing a basement or adding a below-grade bathroom without jackhammering the slab.

Not for: a standard above-grade bathroom that already has a floor drain — that convenience is wasted here.

Heavyweight Champ

11. American Standard Champion 4 One Piece Elongated Toilet, 1.6 GPF, White

4″ Flush ValveSlow-Close Seat

A four-inch flush valve and a wide trapway tuned to be virtually clog-free.

The Champion 4 is built around one idea: never clog. It pairs a large 4-inch flush valve with a 2-3/8-inch fully glazed trapway, and that combination is designed to move waste through with far less resistance. It runs 1.6 GPF, and the smooth one-piece body with the EverClean surface works to stop stain and odor-causing buildup before it starts. The bowl sits at a 16.5-inch chair height, and a slow-close seat is included.

The flush is fast and powerful without a heavy swirl, and the tank refill runs quietly. It is built for a 12-inch rough-in and ships with a chrome trip lever and bolt caps, covered by a limited 10-year warranty.

Two things to know. It weighs 115 pounds — the heaviest toilet on this list — so plan for help getting it onto the floor bolts. And a few shoppers say a large load or heavy toilet-paper use can still call for a second flush. Add a wax ring and hold-down bolts, since those are not in the box. Lean toward a wax-free seal to make the seal-up more forgiving.

The Anti-Clog Argument

  • 4-inch flush valve and 2-3/8-inch glazed trapway push waste through
  • One-piece smooth body with EverClean stain-fighting surface
  • Slow-close seat included; built for a 12-inch rough-in
  • Covered by a limited 10-year warranty

The Weight And Fuss

  • 115 pounds needs two people to set on the bolts
  • Wax ring and floor bolts sold separately

Made for: a busy bathroom where a clog means a bad day, and you want the biggest valve and trapway in one piece.

Think twice if… you are installing solo on a second floor — this is the heaviest toilet here by a clear margin.

Understanding the Specs

GPF And The 1.6 Flush

GPF stands for gallons per flush — the volume of water each press uses. The 1.6 GPF figure is the full-flush rating modern toilets are built to meet, and dual-flush models add a lighter 1.1 GPF press for liquid waste. The lighter press saves water on easy trips while the 1.6 side handles the rest.

MaP Score Explained

MaP is a third-party test that measures how many grams of waste a toilet clears in a single flush. The higher the number, the stronger the single-flush clearing power. Both the HOROW T0338W and the AKNIRL OT-001 carry a 1000g MaP score, which is the benchmark that means one flush does the job.

Rough-In Distance

Rough-in is the measurement from the finished back wall to the center of the floor drain bolts. Most homes run 12 inches, and most toilets here are built for that. The VEVOR W2121-10″ ships on a 10-inch rough-in instead, so match the toilet to your floor rather than assuming every model will fit.

Comfort Height vs Standard Height

Comfort height sits around 17 inches from floor to seat rim, making sitting down and standing up easier for many adults. Standard height ranges from about 15 to 17 inches. The HOROW and AKNIRL both land at 17.3 inches, while the VEVOR sits at 16 inches — so height is a spec worth choosing deliberately.

FAQ

Will a 1.6 GPF toilet actually flush as well as my old one?
It can, and the deciding factor is the flush technology rather than the volume. Toilets like the HOROW T0338W and the AKNIRL OT-001 back their1.6 GPF rating with a 1000g MaP score, which is the widely used benchmark for clearing the bowl in one press. Pressure-assisted models such as the American Standard Cadet use compressed air to drive a stronger, faster flush at the same 1.6 gallons.
What does GPF mean on a toilet and why does 1.6 matter?
GPF means gallons per flush — the water each press uses. The 1.6 GPF figure is the full-flush rating modern toilets meet, and a dual-flush model adds a lighter 1.1 GPF press for liquid waste. Choosing a true 1.6 GPF full flush matters because it keeps enough water moving to clear the bowl, while the lighter press trims water use on the easy trips.
How do I know if I need a 10-inch or 12-inch rough-in toilet?
Measure from the finished back wall to the center of the floor drain bolts. If that distance is about 12 inches, you need a 12-inch rough-in model, which covers most of the toilets here. If it is closer to 10 inches, the VEVOR W2121-10″ is built for that. A 12-inch toilet will not sit against the wall on a 10-inch floor, so measure before ordering.
What is a MaP score and does a higher number mean a stronger flush?
MaP is a third-party test that measures how many grams of waste a toilet clears in a single flush. A higher number means stronger single-flush clearing power. The HOROW T0338W and the AKNIRL OT-001 both carry a 1000g MaP score, which is the practical benchmark that one flush does the job.
Are pressure-assisted toilets louder than gravity toilets?
Yes, they tend to run louder. The American Standard Cadet uses pressure-assisted siphon jet action, where compressed air drives the water out fast and hard, and buyers describe the flush as noticeably loud. Gravity models like the Kohler Highline Classic and the TOTO Drake are quieter overall, though the Kohler still produces a distinct whoosh.
What is the difference between comfort height and standard height?
Comfort height sits around 17 inches from floor to seat rim, which makes sitting down and standing up easier for many adults. Standard height is generally 15 to 17 inches. The HOROW T0338W and AKNIRL OT-001 both measure 17.3 inches, while the VEVOR sits at 16 inches and the American Standard Champion 4 at 16.5 inches.
Do I need extra parts beyond what comes in the box?
It depends on the model. The HOROW T0338W and the AKNIRL OT-001 include a wax ring, floor bolts and the seat. The TOTO Drake ships as bowl and tank only, so you add a seat, a wax ring and flange bolts separately. The American Standard Cadet comes without a seat, and the Champion 4 needs a wax ring and hold-down bolts added to your order.
Can a macerating toilet be used in a basement without a floor drain?
Yes — that is exactly what it is built for. The Simple Project MT-1-400B uses a 500W macerator pump that lifts waste up to 23 feet up and away, so you can place a bathroom below the sewer line. It also has four water inlets so a sink, shower and washing machine can feed into the same system. It lets you add a bathroom without cutting concrete to reach a drain.
How long does a quality one-piece toilet typically last?
There is no single lifespan figure, but the material matters — ceramic and vitreous china bodies like these are built to take years of routine use. Buyers of the TOTO Drake and the Kohler Highline Classic describe dependable service over multi-year stretches. The Champion 4 is backed by a limited 10-year warranty, and the TOTO Drake covers strong performance over a year of no-leak use in owner reports.
Is a one-piece toilet easier to clean than a two-piece?
Generally yes. A one-piece toilet has no gap between the tank and base, so there is no crevice for grime to collect — the HOROW T0338W, the AKNIRL OT-001 and the Abruzzo all use that smooth construction. Two-piece models like the TOTO Drake and the American Standard Cadet bolt the tank on separately, which adds a joint but makes shipping and replacement easier.
Will a dual-flush toilet save water versus a single 1.6 GPF model?
A dual-flush model gives you a choice: a lighter 1.1 GPF press for liquid waste and a full 1.6 GPF press for solid waste. Over time that lets you use less water on the easy trips. Single-flush 1.6 GPF toilets like the TOTO Drake, the American Standard Cadet and the Champion 4 use the full volume every time, which keeps things simple but uses more water.

Final Thoughts: The Verdict

For most bathrooms, the 1.6 gpf toilet that makes the most sense is the HOROW T0338W — it fits a small space, sits you at a 17.3-inch ADA chair height, and backs its 1.1/1.6 GPF dual flush with a 1000g MaP score (a lab measure of how much waste one flush clears). If bowl-clearing is your whole priority, the AKNIRL OT-001 matches that 1000g score with a deeper elongated bowl. Want the bowl to clean itself as it flushes, grab the TOTO Drake. And for a below-grade bathroom where no gravity toilet can reach, the Simple Project macerating system is the one built for the job.

How We Picked

We do not accept paid placement. Every pick is matched to a real buyer and a real use-case; we do not hands-on test units.

Sources & Methodology

Specifications: manufacturer listings and product documentation. Review insights: verified customer reviews, as of September 2026. Pricing: not shown on this page (it changes often); check the current price via the retailer link.

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Mo Maruf

Mo Maruf

Founder

I am a dedicated home cook and appliance enthusiast. I spend hours in my kitchen testing real-world storage methods, reheating techniques, and kitchen gear performance. My goal is to provide you with safe, tested advice to help you run a more efficient kitchen.