How to Measure a Vanity Sink: Bathroom Sink Dimensions & Standard Sizes
By Mikael Short
January 28, 2022
Your vanity sink is an essential component of your bathroom, which is why purchasing a new bathroom sink is one of the most impactful updates you can make to your space.
When searching for a new sink, the last thing you want to do is measure your sink incorrectly—and then order the wrong one! Knowing your bathroom sink dimensions and the correct bathroom sink size is essential to finding the best sink for your space.
Thankfully, this guide will walk you through everything you need to know to find a well-fitting and beautiful new sink for your space. Discover how to measure a bathroom sink, find out standard bathroom sink sizes, and learn how to read important sink dimensions and specs on product pages!
How to Measure a Bathroom Sink
You can determine the sink size you need by measuring the basic sink dimensions and the area surrounding it.
The most important bathroom sink dimensions to measure when looking for a new vanity sink are length (right to left), width (front to back), and depth (top to bottom) in inches. The replacement should match these specifications.
For length and width, measure from one outer sink lip to the opposite side (for most sinks), or from the edge of the counter to the other edge lengthwise (for undermount). For round and oval sinks, measure the diameter, or the length across the widest point of the sink.
For depth, measure from the top of the sink, or where it meets the countertop, to its deepest point.
Consider the space where you’re installing the new sink in as well. Measure the available space (wall and/or countertop) and note where plumbing exits are. On countertops, give a few inches of breathing room around the sink for bathroom necessities, if it’s available.
For undermount or drop-in sinks, make sure there is clearance within your vanity cabinet for the sink height.
Bathroom sink faucet measurements may also be needed to find the perfect matching vanity faucet.
Double Bathroom Sink Dimensions
It’s quite the convenience to have a double vanity sink situation, so ensuring the right fit and measurements are key for ample space so you don’t knock elbows with your partner.
While you may find double bathroom sinks in various sizes, the standard size and shape is circular between 18-20 inches and about 8” deep. The distance between the two sinks, measured from each of their centers, should be at least 30 inches, if not more, depending on the total length of your vanity.
How to Determine Bathroom Sink Size Based on Style
For undermount sinks… Find a sink in the exact shape and size of your existing sink, or you’ll have to resize the cutout opening (which means more cost and more labor).
For drop-in sinks… Ensure at least one inch of clearance between the lip of the sink and the cutout so the lip has somewhere secure to sit. A new vanity drop-in sink cannot be smaller than the cutout.
For wall-mount sinks… Measure the horizontal height and width of the chosen area to find a sink to fit.
For pedestal sinks… Measure both horizontal and vertical space for potential height and width (since you may want it lower or higher depending on who uses it).
For vessel sinks… Any size can work on your countertop so long as the lip of the sink is one inch away from the edge of the countertop. You may also need to plan for room for a faucet addition if it’s not included with the sink. The countertop size will determine what size fits within it.
ADA-Compliant Bathroom Sink Height & Basin Depth
ADA regulations call for a few specifications for bathroom sink dimensions to be compliant.
Sink Height: 34” (or 31” for kids 12 and under)
Basin Depth: 6.5”
Knee clearance beneath the sinks is also important for wheelchair accessibility.
Height: 27” (or 24” for kids 12 and under)
Bathroom Sink Dimensions to Know
When you’re looking for a bathroom sink online, it might be overwhelming to have different specs and measurements that aren’t clear to you. Let’s break down the basic sink dimensions you’ll need to know when shopping for a new bathroom sink. These are all measured in inches.
Basin depth—How deep the basin is. Measure from the deepest point to the lip of the sink.
Basin width—How wide the basin is from left to right. Measure from the edge of the sink wall to the other edge lengthwise.
Basin length—The distance between the back inner wall of the sink to the front inner wall.
Basin shape—Sinks are constructed in a few shape styles, from the classic circle to modern square or rectangle sinks. More unique basin shapes are available based on the sink material.
Sink height—The vertical distance from the bottom to the top of the sink, edge to edge, measured from the exterior.
Sink length—The horizontal distance from left to right on the sink, edge to edge.
Sink width—The total horizontal distance between the front and back of the sink, edge to edge.
Sink shape—The constructed shape of the overall sink.
Height—The total vertical measurement from top to bottom encapsulating the full size.
Sink height applies to specific sink types, such as pedestal sinks, vessel sinks, or wall-mount sinks.
Length—The measurement of the longest side of the sink.
Width—The horizontal distance between the left and right sides of the sink.
Faucet holes—The number of pre-drilled holes for faucet and handles.
Faucet hole size—The size of the faucet installation hole, from edge to edge in the center.
Faucet centers—The distance between the installation holes for faucet handles, measured from the center of the outermost holes.
Drain size—The distance between opposite edges of the drain.
Drain connection—The distance between edge to edge for the connection.
Drain placement - Where the drain is installed during construction (rear, center, front, etc).
Armed with these terms and your measuring tape, you’ll be able to find the right size vanity sink for your bathroom.
A New Vanity Sink… Ready, set, go!
Shopping for a new or replacement vanity sink for your bathroom can be super easy when you know what size you’re looking for. We hope this guide to measuring and sink sizes helps you along your way to finding that perfect fit. As always, consider what’s proportionate to your vanity cabinet, countertop, or bathroom, and let your personal style show through a sink to match your tastes too!
If you’d like assistance with remodeling or redesigning your bathroom, our expert designers are here to help!