Bathroom Mirror Size Calculator

Quick answer

The bathroom mirror size calculator works out the maximum width and height of a rectangular, round or double mirror for your vanity, leaving the recommended clearance at the sides and above the vanity.

Mirror width (each)
32
Maximum mirror height
50
Bottom edge above counter
6

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

  1. Mirror type
  2. Vanity width
  3. Vanity height
  4. 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.

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) ÷ 2 Round mirror diameter = vanity width − 4 in

Worked 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.

Cite this calculator

Speedy Calculator. (2026). Bathroom Mirror Size Calculator. Speedy Calculator. https://speedycalculator.com/calculators/everyday-life/bathroom-mirror-size/