Bathroom Sizes
Calculators for the measurements a bathroom comes down to: the vanity that fits the wall, the mirror and lights over it, the shower curtain and its rod, the bath mat on the floor, and the fan and light the room needs.
The vanity
Find the vanity that fits your wall with room in front of it and beside the toilet, then size the mirror over it, or one for each sink, and the lights.
In the shower
Size the shower curtain for a tub or a stall, with the liner to match, and find how high to hang the rod.
On the floor
Size the bath mat beside the tub or outside the shower, or a mat or runner in front of the vanity.
Air and light
Find how many CFM the exhaust fan should move and the duct it needs, then work out how much light the bathroom needs; choose Bathroom as the room type.
Start with the mirror
A bathroom mirror is sized from the vanity under it, not from the wall. The vanity mirror size calculator takes the vanity's width and works out the mirror width to look for: a little narrower than the vanity, never wider, and the standard size that lands closest to the right proportion. On a double vanity it sizes one mirror for each sink, centered over it, so the pair stays inside the vanity.
Height matters as much as width. The calculator places the bottom edge a few inches above the counter, clear of the faucet and the splashes, and the top far enough above eye level that everyone who uses the mirror sees their whole face. From those two edges it gives the height to shop for.
Lights at the vanity
Light at the mirror is about your face, not the counter. The calculator also says where a light bar above the mirror or a pair of sconces beside it should go, so the fixture you pick fits the mirror you pick.
For the room as a whole, a bathroom needs more light than a bedroom or a living room. The room lumens calculator turns the room's size into the lumens to plan for: choose Bathroom as the room type.
The shower curtain
A shower curtain is sized from the shower and the rod, not from the label that says standard. The shower curtain size calculator takes the width wall to wall and the rod's height, and works out the standard curtain that covers the opening with folds to spare and ends just above the floor: clear of it, so it doesn't gather mildew, and low enough to keep the water in the tub.
It also says where a new rod goes for that curtain and which liner hangs inside the tub, and it sizes a curtain for a shower stall, where there's no tub to catch the water and the curtain runs nearly to the floor.
How these tools work
Each calculator states the rule it uses and the assumptions behind it, right on the page under "How we calculate." The result is a starting point you can adjust to the people who use the room.
Everything runs in your browser: the numbers you type stay on your device. Use Copy link to save a result or send it to someone helping you shop.
