Choose a bathroom vanity mirror by measuring the clear wall, checking who uses the basin and testing the outline. A slightly narrower mirror often leaves a pleasing border around a vanity, but fixed “2–4 inch” rules cannot account for every basin, frame, wall light or room. Use proportions as a starting point, then confirm the practical fit.
Measure the vanity and the space above it
Record the full vanity width, basin positions, tap height and clear wall dimensions. Include lights, side walls, tile features and any ceiling slope. A basin bowl is narrower than the cabinet around it, so decide which element the mirror is intended to align with.
The bathroom mirror size calculator gives a useful estimate from your measurements. Follow it with a paper outline or removable tape on the wall so you can judge the actual reflection height and surrounding space.
Compare three sizes with different proportions
50 × 80 cm long oval mirror — £99. A narrower, taller outline. On a 70 cm vanity it leaves 10 cm on each side when centred, if the wall and basin layout suit that arrangement.
80 cm round backlit mirror — £179. On a 100 cm vanity it also leaves 10 cm each side at its widest point. The circular reflection narrows towards the top and bottom, unlike a rectangle.
120 × 60 cm double-light mirror — £249. A wider format to test above a 140 cm vanity. Check the basin positions and intended mounting orientation before settling on it.
Prices and stock checked on 27 October 2026. Listed prices are before any checkout promotion.
These are examples of the spacing calculation, not minimum clearances or universal design rules. The product’s installation requirements and your actual layout still determine the final position.
One mirror or two above a double vanity?
A continuous mirror can connect the two basins visually; two individual mirrors can frame each user’s position. Mark both arrangements and compare the reflections, wall lights and central gap. A double vanity does not automatically require one particular mirror width.
Browse large mirrors for a continuous reflection if you prefer a wide design. For separate curved outlines, compare round mirrors with the distance between basin centres.
Set height around the users, not one standard number
Stand at the basin and check the shortest and tallest regular users. The reflection should be comfortable without leaning or stretching. Include the tap, backsplash, door swing if using a cabinet, and any light above the mirror.
A fixed gap above the tap or a single floor-to-centre height can leave the mirror too high for someone. A taller mirror may accommodate more users, but two side-by-side mirrors do not automatically solve a height problem.
Account for frames, light and depth
Use the overall product dimensions, including the frame, rather than adding an assumed frame allowance. Frame widths vary. A bold frame changes the visual weight even when the outside dimensions match a frameless model.
For backlit mirrors, include the specified rear and surrounding clearances so the glow and ventilation work as designed. Do not size the installation from a photographed halo. Leave appropriate space around wall lights and fittings for the actual products.
Check the final outline before ordering
- View the outline from the doorway as well as at the basin.
- Test the reflection height for regular users.
- Confirm the overall dimensions and orientation of the selected size.
- Allow room for nearby lights, taps and any cabinet door.
- Plan wall support and the electrical connection before fitting.
Our guides for a cloakroom vanity, an 800 mm vanity and a 1000 mm vanity explore common layouts in more detail.
Once the outline works, browse LED Mirror World for the finish and functions you enjoy. The right size should feel balanced on the wall and comfortable to use every morning.