Size the fixture to your mirror, mount it roughly 3 inches above the glass or 75–80 inches off the floor, and make sure the fixture is damp- or wet-rated for where it hangs.
A vanity light that’s too small leaves half your face in shadow at 6 a.m., and one mounted too high throws light onto the ceiling instead of your chin. The fix comes down to three decisions: width, height, and rating. Get those right and the grooming light in your bathroom stops being a guessing game.
How Wide Should the Light Be Compared to the Mirror?
For a single fixture over the mirror, the light should never extend wider than the mirror it sits above — that’s the one rule nearly every retail guide repeats. Beyond that floor, opinions split: Lumens and LightsOnline allow anywhere from about one-third of the mirror’s width up to roughly 75%–100%, while the stricter guidance from Home Depot keeps the fixture at or under the mirror’s full width.
The practical middle ground most designers land on is one-third to three-quarters of the mirror width, centered on the glass. A 36-inch mirror, for example, takes a fixture somewhere between 12 and 27 inches wide. Wider than the mirror looks top-heavy; much narrower and you lose even wash across the face.
For a double vanity, you have two good options:
- Two matching above-mirror lights — one centered over each sink’s mirror.
- Two sconces per sink — one flanking each side of the glass for the flattest light.
A long multi-light bar over a wide counter works too, but LightsOnline’s guide warns it should stay at roughly three-quarters of the mirror width and no wider than the cabinet below it.
What Height Should a Vanity Light Be Mounted?
For an above-mirror fixture, the target is 75–80 inches from the finished floor to the center of the light fixture, according to Home Depot’s mounting guide. A second common approach from Lumens places the bar about 3 inches above the top edge of the mirror, which keeps the light hitting your face instead of arcing over your head.
Side-mounted sconces sit at a different height entirely. Because they light the face from the sides, they land at eye level — roughly 60–70 inches from the floor, with sconces spaced about 28–30 inches apart on a symmetric layout.
If you’re sizing your mirror and cabinet at the same time, a roundup of bathroom vanities with mirror and lights already paired can save you the fitting math later — tested vanities with integrated lighting.
Damp or Wet Rated: Which One Belongs in Your Bathroom?
Every bathroom fixture needs at least a damp-location rating — that covers the humidity that hangs in the air after a shower. Fixtures hanging inside or directly above a shower enclosure or tub, though, sit in what the NEC defines as a wet zone under Article 410.10, and those must carry a wet-location listing.
A standard vanity bar mounted over a mirror away from the tub, per that same code guidance, generally only needs the damp rating. Check the label on the fixture before you buy; the rating is printed on the box and on the fixture itself.
| Spot | Right Height | Rating Needed |
|---|---|---|
| Over the mirror | 75–80 in. to fixture center | Damp |
| Above mirror (alt.) | ~3 in. above glass | Damp |
| Side sconces | 60–70 in. from floor | Damp |
| Sconce spacing | 28–30 in. apart | Damp |
| Inside shower | Per local code | Wet |
| Directly above tub | Per local code | Wet |
What Light Quality Should You Look For?
Retail guides settle on two specs for a grooming light: a neutral color temperature around 2700K–3000K and a color rendering index (CRI) of 90 or higher. The first keeps skin tones from looking orange or blue; the second keeps makeup and beard lines reading true.
Three mistakes kill more bathroom lighting than anything else. A fixture wider than the mirror or cabinet looks unbalanced. Mounting too high pushes light up toward the ceiling instead of down onto your face. And relying on a single centered bar when two sconces would light the face from the sides leaves harsher shadows on the nose and jaw. Mirror-mounted fixtures add another wrinkle — the glass shop has to drill the mirror and a solid backer has to carry the load, per Lumens’ guide, so plan that in advance if you’re going that route.
References & Sources
- The Home Depot. “Vanity Light Height.” Mounting height and width guidance for above-mirror fixtures.
- Lumens. “Bathroom Vanity Lighting Buyer’s Guide.” Sizing, sconce placement, and color-temperature recommendations.
- LightsOnline. “The Complete Bath Light Sizing Guide.” Proportions for single and double vanities, multi-light bars.
FAQs
Can I mount a light directly on the mirror?
Yes, but it takes prep. A glass shop has to drill the mirror for the mounting holes, and there must be a solid backer behind the glass to carry the fixture’s weight. Standard mirror adhesive alone won’t hold a light. If you don’t want that work, keep the fixture on the wall above the glass instead.
Do I need a wet-rated light above my shower?
Yes. Any fixture inside or directly above a shower enclosure or tub sits in the wet zone defined by NEC Article 410.10, and it must carry a wet-location listing. A regular vanity bar away from the tub usually only needs a damp rating, which covers the humidity a bathroom produces.
Is one light above the mirror enough?
It’s often sufficient, but two sconces flanking the mirror give flatter light with fewer shadows across the nose and jaw. If you can only fit one fixture, keep it centered on the mirror and roughly one-third to three-quarters of the mirror’s width so the wash stays even.
