Bathroom Mirror Size Calculator
A mirror that is much wider than your vanity can look out of place, while one that is too narrow leaves the wall above the basin looking bare. Enter your vanity or basin width below to get a recommended mirror width range.
Find the right bathroom mirror width
Enter your vanity or basin width to get a recommended mirror width range.
For a balanced look above your vanity, aim for a mirror width of:
64cm - 80cm
A mirror roughly the same width as the vanity, or a little narrower, looks best — avoid going significantly wider.
Recommended products
A few well-reviewed bathroom mirrors at a range of widths.
- 13cm Diameter
£45.99
Pros
- Built-in LED light ring for clearer close-up viewing
- 3x magnification suits shaving and makeup application
- Battery operated — no wiring needed
Cons
- Small size means it suits close-up tasks rather than full-face viewing
- 18cm Diameter
£54.00
Pros
- Traditional tilting design adjusts to the angle you need
- Chrome finish suits classic bathroom suites
- Sturdy wall-mounted extending arm
Cons
- Smaller mirror face than modern LED wall mirrors
- 60cm Diameter
£54.99
Pros
- Anti-fog demister pad keeps the mirror clear during showers
- Touch sensor control for the cool-white LED ring
- IP44 rated for safe bathroom use
Cons
- Requires a mains or transformer connection for the LED lighting
Frequently asked questions
Should my bathroom mirror be the same width as the vanity?
It does not need to match exactly — a mirror somewhere between 80% and 100% of the vanity width usually looks best, giving a balanced look without the mirror overhanging the unit below it.
What happens if the mirror is much wider than the vanity?
A mirror that is significantly wider than the vanity below it can look out of proportion and may not leave enough wall space for wall lights or storage on either side, so it is worth staying close to the vanity width.
Can I use a smaller mirror than the calculator suggests?
Yes, a narrower mirror can still work well, particularly in a compact bathroom, though very small mirrors relative to the vanity can look a little lost above a wider unit.
Does mirror height matter as much as width?
Height matters for practicality, since the mirror needs to comfortably show your face and shoulders for the tallest regular user, but width is the main factor for how the mirror looks in proportion to the vanity below.
How this calculator works
The calculator takes the width of your vanity or basin unit and calculates a recommended mirror width range of 80% to 100% of that width. So for an 80cm vanity, the recommended mirror width is 64cm to 80cm. This range is based on interior design principles that suggest a mirror should roughly match or be slightly narrower than the vanity below it for a balanced, proportional look.
The 80% lower bound ensures the mirror doesn't look too small or lost above a wide vanity, while the 100% upper bound prevents the mirror from overhanging or looking wider than the unit below. If you have a very large vanity (over 120cm), you might consider two smaller mirrors instead of one wide one, or a mirror with a built-in shelf or cabinet for extra storage.
Bathroom mirror sizes and common vanity widths
| Vanity width | Recommended mirror width | Mirror type | Typical use |
|---|---|---|---|
| 60cm | 48-60cm | Small round or rectangular | Cloakroom, small ensuite |
| 70cm | 56-70cm | Compact rectangular | Small bathroom, guest WC |
| 80cm | 64-80cm | Standard rectangular | Standard bathroom, family |
| 100cm | 80-100cm | Large rectangular or oval | Main bathroom, master ensuite |
| 120cm | 96-120cm | Extra wide or double mirror | Large ensuite, his-and-hers |
Worked example: A 100cm vanity unit
For a 100cm wide vanity, the calculator recommends a mirror between 80cm and 100cm wide. A 90cm mirror would sit centrally above the vanity with 5cm of clearance on each side, giving a balanced, proportional look. If you have wall lights on either side, make sure the total width of mirror plus lights doesn't exceed the vanity width plus 10-15cm on each side.
If your bathroom has a 120cm vanity, you might choose a single 120cm mirror for a seamless look, or two 60cm mirrors side by side for a more flexible arrangement. Two mirrors can be useful if you share the bathroom with a partner — each person gets their own reflection without the mirror being wider than the vanity.
Common mistakes when choosing a bathroom mirror
- Buying a mirror that's too wide for the vanity. A mirror that overhangs the vanity by more than a few centimetres looks out of proportion and can make the bathroom feel unbalanced. Stick to the 80-100% rule for a harmonious look.
- Forgetting to account for taps and fixtures. A tall mixer tap or a wall-mounted tap can extend 15-20cm above the vanity surface. Make sure the mirror is high enough to clear the tap, or choose a mirror with a curved or notched bottom to fit around it.
- Ignoring the height of the users. A mirror that's positioned too high or too low for the tallest and shortest users in the household is frustrating. The centre of the mirror should be roughly at eye level for the average user, typically 150-160cm from the floor. If you have a very tall or short household member, consider a tilting mirror or one that can be positioned at a custom height.
- Not considering lighting. A mirror without adequate lighting around it can cast shadows on your face, making shaving or applying makeup difficult. If you don't have space for side lights, choose a mirror with an integrated LED light strip — it provides even, shadow-free illumination and is especially useful in bathrooms with poor natural light.
What to look for when buying a bathroom mirror
Mirror coating matters for durability. A good bathroom mirror should have a silver or aluminium backing sealed with copper-free paint to prevent tarnishing and black spots. Cheap mirrors without proper sealing can develop black edges or spots within a few years, especially in a steamy bathroom. Look for mirrors specifically labelled as 'bathroom safe' or 'IP44 rated' for use in wet zones.
Frame style affects both look and maintenance. A frameless mirror looks modern and is easy to clean, but the edges can chip if mishandled. A framed mirror in a moisture-resistant material (aluminium, stainless steel, or treated wood) protects the edges and can add a design feature. Avoid mirrors with fabric or untreated wood frames in bathrooms — they absorb moisture and can mould.
Finally, think about extra features. A demister pad behind the mirror prevents it from steaming up after a shower — it's a cheap and effective upgrade that costs very little to run. An integrated shaver socket, LED light strip, or Bluetooth speaker can add convenience, but they need a power supply behind the mirror, which must be installed by a qualified electrician to IP44 standards.
More questions answered
Should my bathroom mirror be the same width as the vanity?
It does not need to match exactly — a mirror somewhere between 80% and 100% of the vanity width usually looks best, giving a balanced look without the mirror overhanging the unit below it.
What happens if the mirror is much wider than the vanity?
A mirror that is significantly wider than the vanity below it can look out of proportion and may not leave enough wall space for wall lights or storage on either side, so it is worth staying close to the vanity width.
Can I use a smaller mirror than the calculator suggests?
Yes, a narrower mirror can still work well, particularly in a compact bathroom, though very small mirrors relative to the vanity can look a little lost above a wider unit.
Does mirror height matter as much as width?
Height matters for practicality, since the mirror needs to comfortably show your face and shoulders for the tallest regular user, but width is the main factor for how the mirror looks in proportion to the vanity below.
Should I get a round or rectangular mirror?
It depends on your bathroom style. Round mirrors soften the look of a bathroom with lots of straight lines and can make a small bathroom feel less harsh. Rectangular mirrors are more traditional and practical — they give a larger viewing area for the same width and work well above standard vanities. For a modern bathroom, a rounded rectangle or oval mirror can be a good compromise.
What is a demister pad and do I need one?
A demister pad is a thin heating element behind the mirror that prevents it from steaming up after a shower. It's especially useful in bathrooms without a window or with poor ventilation. A typical demister pad uses 50-100W and costs about 1-2p per hour to run — you can plug it into a timer or switch so it only comes on when needed.
Can I install a bathroom mirror myself?
If the mirror has no electrical features and you're comfortable drilling into tiles, yes — use a spirit level to get it straight, mark the fixing points, and use appropriate wall plugs and screws for tile. If the mirror has a demister, light or shaver socket, you'll need a qualified electrician to install the wiring to IP44 bathroom safety standards. Never attempt DIY electrical work in a bathroom unless you're fully qualified.
How high should I hang a bathroom mirror?
The centre of the mirror should be roughly at eye level for the main user, typically 150-160cm from the floor. If you have a very tall or short household member, adjust accordingly — the mirror should show your face and shoulders without you having to crane your neck. For a vanity with a tall mixer tap, make sure the bottom of the mirror clears the top of the tap by at least 5-10cm.