Quick Answer
Width: a vanity light bar should span roughly 75% of the mirror's width — never wider than the mirror itself. A 36 in mirror takes a 24-28 in bar; a 48 in mirror takes a 36 in bar.
Height: a bar above the mirror mounts at 75-80 in from the floor, or 6-8 in above the mirror's top edge. Sconces flanking the mirror mount at 60-66 in to centre — roughly eye level.
Spacing for side sconces: 28-40 in apart, which puts one on each side of a standard mirror. Side placement is what removes shadows from the face; a fixture above the mirror casts them downward.
Output: aim for 1,500-2,500 lumens total at the vanity, at 2700-3000K for a warm bathroom or up to 3500K where accurate colour matters for grooming. CRI 90 or better.
Vanity lighting is the one fixture in a house that has to do a real job every day, and most of the decisions that determine whether it works are dimensional rather than stylistic. A beautiful bar at the wrong width looks wrong against the mirror; the right fixture at the wrong height throws shadows exactly where you need to see. This guide covers the sizing ratios, the mounting heights for each configuration, the shadow physics behind side-versus-above placement, and the output and rating specifications that decide whether the fixture belongs in a bathroom at all.
On this page
- Why Placement Matters More Than the Fixture
- Width: The 75% Rule
- Mounting Heights by Configuration
- Sconce Spacing and Mirror Width
- Sizing by Vanity Width
- Double Vanities
- Output, Colour Temperature and CRI
- Damp, Wet and the Zones That Govern Them
- Vanity Light Is Not the Whole Plan
- Powder Rooms and Small Baths
- Common Mistakes
- Frequently Asked Questions
Why Placement Matters More Than the Fixture
The bathroom mirror is the only place in a house where lighting has to illuminate a face straight on. Everywhere else, light from above is fine — it lights the room and shadows fall onto surfaces where nobody is looking. At a mirror, light from above falls into the eye sockets, under the nose and beneath the chin, which is exactly where you need to see for shaving, makeup and anything else done at close range.
This does not make bars wrong. Side sconces need wall space beside the mirror, which many bathrooms do not have — a mirror running the full width of a vanity leaves nowhere to put them. In that case a bar above is the correct answer, and the shadow problem is reduced by choosing a fixture with diffused shades facing forward rather than bare lamps facing down.
Width: The 75% Rule
A vanity bar should span roughly 75% of the mirror's width, and never exceed the mirror itself. That single ratio settles most sizing questions.
| Mirror width | Bar width (75%) | Acceptable range |
|---|---|---|
| 24 in | 18 in | 16-22 in |
| 30 in | 22 in | 20-28 in |
| 36 in | 27 in | 24-34 in |
| 42 in | 32 in | 28-40 in |
| 48 in | 36 in | 32-46 in |
| 60 in | 45 in | 40-58 in |
| 72 in | 54 in | 48-70 in |
Two adjustments. A bar wider than the mirror reads as a mistake even when it is centred, because the eye compares the two edges directly — this is the most common vanity sizing error. And where the mirror is much wider than the vanity beneath it, size the bar to the vanity rather than the mirror, since the counter is what the light is actually serving.
Mounting Heights by Configuration
A bar mounts by the mirror's top edge; sconces mount at eye level and are spaced by the mirror's width
| Configuration | Height from floor | Reference measurement |
|---|---|---|
| Bar above mirror | 75-80 in to fixture | 6-8 in above the mirror's top edge |
| Sconces beside mirror | 60-66 in to centre | Roughly eye level for a standing adult |
| Sconces on the mirror itself | 60-66 in to centre | Requires a mirror rated for surface mounting |
| Pendants flanking a mirror | Bottom at 60-68 in | Clear of the counter and of the mirror's edge |
| Ceiling fixture over vanity | Standard ceiling height | Supplementary only — shadows worst from directly above |
Where the ceiling is 8 ft, the 75-80 in figure leaves little room above a tall mirror — check the mirror's top edge before choosing the bar, since a fixture that will not fit above it forces the decision back to side sconces or a shorter mirror. Full placement figures across every room are in our light fixture height chart.
Sconce Spacing and Mirror Width
For side sconces the spacing is set by the mirror: mount one on each side, 28-40 in apart measured centre to centre. That range covers mirrors from roughly 20 to 32 in wide with the fixtures sitting 3-6 in clear of the mirror's edge.
- Leave 3-6 in between the mirror edge and the fixture. Closer and the sconce crowds the mirror; further and it stops lighting the face and starts lighting the wall.
- Match the pair exactly. Both fixtures are seen in one glance, so any difference in height or projection reads immediately. Measure from the floor for both rather than from the mirror, in case the mirror is not level.
- Wide mirrors change the answer. Above about 40 in of mirror width, side sconces sit too far apart to light the face from both sides — that is the point where a bar above becomes the better solution, or where the mirror should be split into two.
- Check the projection. A sconce projecting more than 4-5 in from the wall becomes something people knock in a narrow bathroom.
Sizing by Vanity Width
Where the mirror size is not yet decided, work from the vanity — the counter is the fixed element in most bathroom plans.
| Vanity width | Typical mirror | Bar option | Sconce option |
|---|---|---|---|
| 24 in (powder room) | 20-22 in | 16-18 in | Single sconce, or pair if wall allows |
| 30 in | 24-28 in | 20-22 in | Pair at 30-34 in apart |
| 36 in | 30-34 in | 24-28 in | Pair at 34-38 in apart |
| 48 in | 40-44 in | 32-36 in | Pair at 44-48 in — getting wide |
| 60 in (single sink) | 48-54 in | 40-44 in | Bar preferred at this width |
| 60-72 in (double sink) | Two mirrors | Two bars, one per mirror | Three sconces — see below |
Double Vanities
Two sinks introduce a layout question with three workable answers, and one that looks tidy on paper but fails in use.
Two mirrors, two bars is the most straightforward: each mirror gets its own fixture sized to it, and the two read as a matched pair. Three sconces — one at each outer edge and one between the mirrors — is the more considered option, since the centre fixture serves both sides and the arrangement reads deliberate. Four sconces, two flanking each mirror, gives the best light of all and needs the most wall.
What does not work is a single long bar spanning both mirrors. It looks orderly, but each user stands off-centre relative to it, so the light arrives at an angle and the shadow problem returns — which is the specific thing vanity lighting exists to solve.
Output, Colour Temperature and CRI
Three numbers decide whether the light works, and none of them is about the fixture's appearance.
- Total output: 1,500-2,500 lumens at the vanity. That is the whole vanity zone rather than per fixture — a 4-light bar at 450 lumens each lands at 1,800, which is right for a standard bathroom. Powder rooms can run lower; a primary bath with a dark finish needs the upper end.
- Colour temperature: 2700-3000K for warmth, up to 3500K for accuracy. The trade is real. Warmer light is more comfortable and flatters skin; slightly cooler light renders colour more accurately, which matters for makeup application. 3000K is the safe middle for most bathrooms.
- CRI 90 or better. This matters more in a bathroom than anywhere else in the house, because you are judging colour on your own face. Below CRI 90, makeup matched at the mirror looks different in daylight.
- Dimming. A bathroom used at 6am and at 11pm needs two different light levels. A dimmer costs little and is the single most-appreciated addition to a vanity circuit.
- Diffusion. Frosted or opal shades rather than bare lamps. At mirror distance a clear bulb sits directly in the field of view, which is uncomfortable and defeats the purpose.
Damp, Wet and the Zones That Govern Them
Bathroom fixtures are governed by proximity to water, and the requirement is not a preference.
- Damp rated — tolerates humidity and condensation but not direct water. This covers the vanity area in a normal bathroom, which is what most vanity lights are built for.
- Wet rated — required inside a shower or directly above a tub, where the fixture can be hit by water.
- Dry rated — interior fixtures with no moisture rating. These do not belong in a bathroom at all, however well they would suit it.
Zone dimensions vary by jurisdiction, so confirm locally rather than assuming — the general principle is that a defined area around and above a tub or shower requires wet-rated fixtures, and everything else in the room requires at least damp rating. Where a fixture's listing does not state a rating, treat it as dry rated. Rated designs are collected in our bathroom wall lights collection.
Vanity Light Is Not the Whole Plan
A vanity fixture lights the mirror zone. It does not light the room, and a bathroom lit only at the mirror has a bright face-height band and shadow everywhere else.
The working plan is two or three layers. Mirror lighting as described above. Ambient ceiling light — a flush mount, semi-flush or small chandelier, centred in the room or over the main floor area, to fill the space. And in larger bathrooms, a third element: a wet-rated fixture in the shower, or a decorative fixture over a freestanding tub, which is where a small chandelier belongs if the room can take one.
Keep every fixture in the room at the same colour temperature. Mixed Kelvin in a small tiled space is unusually visible, because hard reflective surfaces show the difference in a way soft furnishings do not. The full layered approach is in our bathroom lighting ideas guide, with fixture picks in the vanity lights and sconces guide.
Browse bathroom lighting
Damp-rated vanity and mirror fixtures, plus the full room plan.
Bathroom Wall Lights → Bathroom Lighting → Wall Sconces →Powder Rooms and Small Baths
Small bathrooms invert one of the rules above. In a powder room the mirror is frequently narrow and the walls beside it are tight, which rules out a pair of sconces — but a powder room is also the room where the lighting is most decorative, since nobody applies makeup in a guest bathroom.
Two approaches work. A single small bar above a narrow mirror, sized at 75% as usual, keeps everything conventional. Or a single decorative sconce mounted to one side, which reads as a design decision rather than a compromise and lights the face adequately for a room used briefly. Output can drop to 800-1,200 lumens here, and warmer light at 2700K suits a space designed to feel welcoming rather than functional.
Common Mistakes
- A bar wider than the mirror. The most common vanity sizing error. Target 75% of the mirror's width and never exceed it.
- Mounting the bar too high. Above 80 in the light starts washing the wall rather than the face. Use the 6-8 in above the mirror figure as the check.
- One long bar over a double vanity. Each user stands off-centre, so the light arrives at an angle and the shadow problem returns.
- Bare lamps at mirror distance. A clear bulb sits directly in the field of view. Frosted or opal shades.
- Ignoring CRI. Below 90, makeup matched at the mirror looks different outdoors. This matters more in a bathroom than anywhere else.
- Mixed colour temperatures. Hard tiled surfaces show the difference far more than soft furnishings do. One target for the whole room.
- Assuming any fixture can go in a bathroom. Dry-rated fixtures do not belong there. Damp rating minimum, wet rating near tub and shower.
- Treating vanity light as the room's lighting. It lights the mirror zone. Add an ambient ceiling layer or the room reads as a bright band in a dark space.
- Sconces too close to the mirror. Leave 3-6 in clear of the edge, or the fixture crowds the glass and lights it rather than the face.
Frequently Asked Questions
What size vanity light do I need for a 36 inch mirror?
Roughly 27 in — the target is 75% of the mirror's width, with 24-34 in an acceptable range. Never wider than the mirror itself, since the eye compares the two edges directly.
How high should a bathroom vanity light be mounted?
A bar above the mirror mounts at 75-80 in from the floor, or 6-8 in above the mirror's top edge. Sconces beside the mirror mount at 60-66 in to centre, which is roughly eye level for a standing adult.
Should vanity lights go above or beside the mirror?
Beside, where the wall allows. Shadows fall opposite the light source, so a fixture above puts them under the eyes, nose and chin — while sconces on both sides each fill the shadow the other casts. A bar above is the correct answer where there is no wall space beside the mirror.
How far apart should bathroom sconces be?
28-40 in apart, centre to centre, with 3-6 in clear of the mirror's edge on each side. Above about 40 in of mirror width the sconces sit too far apart to light the face from both sides, and a bar becomes the better answer.
How many lumens does a bathroom vanity need?
1,500-2,500 lumens total at the vanity zone rather than per fixture. A 4-light bar at 450 lumens each lands at 1,800, which suits a standard bathroom. Powder rooms can run lower at 800-1,200.
What colour temperature is best for a bathroom?
2700-3000K for warmth and comfort, up to 3500K where accurate colour rendering matters for makeup. 3000K is the safe middle. Keep every fixture in the room at the same target, since tiled surfaces show mixed Kelvin more than soft furnishings do.
Why does CRI matter at a bathroom mirror?
Because you are judging colour on your own face. Below CRI 90, makeup matched at the mirror looks different in daylight. It matters more here than in any other room.
What lighting works for a double vanity?
Two mirrors with a bar each, three sconces with one between the mirrors, or four sconces flanking each mirror. What does not work is one long bar spanning both — each user stands off-centre, so the light arrives at an angle and shadows return.
Do bathroom lights need a special rating?
Yes. Damp rating is the minimum anywhere in a bathroom, and wet rating is required inside a shower or directly above a tub. Dry-rated fixtures do not belong in a bathroom at all. Zone dimensions vary by jurisdiction, so confirm locally.
Can I use a chandelier in a bathroom?
Over a freestanding tub or in the open floor area, yes, provided it is damp rated and clear of the wet zone your local code defines. It works as the ambient or decorative layer rather than as the vanity light, which still needs to be at the mirror.
What size vanity light for a 48 inch vanity?
With a 40-44 in mirror, a 32-36 in bar. A pair of sconces would sit 44-48 in apart at that width, which is at the outer limit of useful side lighting — the bar is usually the better answer above 48 in.
Should bathroom vanity lights be dimmable?
Ideally yes. A bathroom used at 6am and at 11pm needs two different light levels, and a dimmer is the least expensive and most appreciated addition to a vanity circuit.
Measure the Mirror First
Almost every vanity lighting decision follows from the mirror: its width sets the fixture width at 75%, its top edge sets a bar's height, and the wall beside it decides whether sconces are possible at all. Get those three right and the remaining choices — finish, style, shade shape — are free to be about appearance. Get them wrong and no fixture will look correct in the space.
Browse the range: bathroom wall lights, bathroom lighting, wall sconces.
