A bathroom mirror usually looks best a few inches narrower than the vanity, centred above it, with its bottom edge 5–10 in above the counter and room left for lights above. On double vanities, two mirrors centred over each sink look balanced.
How to use the Bathroom Mirror Size Calculator
- Mirror type
- Vanity width
- Vanity height
- Ceiling height
Results update as you type, and every field accepts the units shown in its menu.
How it works
Choose the mirror type and enter the vanity width, the vanity (counter) height and the ceiling height.
Tips
- Use the figures from your own bills and product labels – prices and appliance ratings vary widely.
- Look at yearly totals: small daily costs add up and make it easier to compare options.
- Round quantities up to whole packs, rolls or bulbs when you shop.
- Re-check the numbers when prices change; most results scale directly with the unit price.
Common mistakes to avoid
- Confusing watts (power) with watt-hours or kilowatt-hours (energy).
- Comparing prices without bringing them to the same unit first.
- Ignoring one-off costs such as installation, delivery or replacement parts.
Inputs explained
| Field | What to enter |
|---|---|
| Mirror type | Choose one: Rectangular, Round, Two mirrors (double vanity) |
| Vanity width | Units: in, cm, ft, m |
| Vanity height | Units: in, cm, ft, m |
| Ceiling height | Units: in, cm, ft, m |
Example values
How the main result changes when Vanity width changes and everything else stays at the example values above:
| Vanity width (in) | Mirror width (each) (in) |
|---|---|
| 18 | 14 |
| 27 | 23 |
| 36 | 32 |
| 45 | 41 |
| 54 | 50 |
| 72 | 68 |
Formula
Rectangular width = vanity width − 4 in; height = ceiling − vanity height − 12 in (max)Double vanity: each mirror = (vanity width − 8 in) ÷ 2Round mirror diameter = vanity width − 4 inWorked example
Inputs — Mirror type: Rectangular; Vanity width: 36 in; Vanity height: 34 in; Ceiling height: 96 in.
Results — Mirror width (each) = 32 in; Maximum mirror height = 50 in; Bottom edge above counter = 6 in.
Frequently asked questions
How wide should a bathroom mirror be?
A few inches narrower than the vanity – for a 36 in vanity, about 32 in.
How high should a bathroom mirror hang?
Centre it at about eye level (60–65 in from the floor), with the bottom 5–10 in above the counter.
Should the mirror match the faucet?
Centring the mirror on the faucet looks best, especially on single-sink vanities.
What formula does the Bathroom Mirror Size Calculator use?
Rectangular width = vanity width − 4 in; height = ceiling − vanity height − 12 in (max).