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.
The most common bathroom vanity widths are 24, 30, 36, 48, 60, and 72 inches. For single-sink cabinets, the average bathroom vanity width range is between 30 and 48 inches. For double vanities, a width range of 60 to 72 inches is standard.
If you're purchasing a vanity without a top, you'll also need to measure for the countertop. Measure the width and depth of the vanity cabinet. The vanity top should be 1 inch wider and 1 inch deeper than the vanity cabinet. Be sure to include allowances for fillers, if you plan to use them.
For a single vanity, the most popular widths are 24", 30", 36", 48", and for double vanities the most popular widths are 60" and 72", but start at 48". The standard depth of a vanity is typically around 20", but narrower options are available. The standard vanity height is 32", but ranges from 30" – 36".
Standard bathroom vanities are generally available in the following widths (presented here in inches): 24, 30, 36, 48, 60, and 72. When it comes to vanity heights, you won't find a standard height per se, but you will typically encounter vanities that average between 32 and 36 inches tall.
On average, a smaller vanity unit has a width of 400-500mm, and a depth of 250mm-450mm depending on the design you choose.
Start by measuring the depth of your cabinet. Place your tape measure along the bottom of the cabinet and measure from the back to the front edge. Next, measure the total width. Place your tape measure along the bottom of the cabinet to measure from the left edge to the right edge.
A 30-inch wide or a 36-inch wide cabinet are most common. The height of the cabinet can be customized, but 36 inches is average. A typical 33 x 22-inch sink will fill a 36-inch base cabinet. If you're replacing a sink, make sure it fits the existing cutout.
30 inches- Used for single basin sinks. 33 inches- Used for offset sinks, or double basin sinks. 36 inches- Used for double basin sinks. 42 inches- This is the largest width in a base cabinet.
If you're replacing an existing sink with the same style, simply measure the length, width, and depth of your current sink and choose a replacement with the same measurements. If choosing a new style, measure the length and width of your vanity's existing cutout, along with the depth of your old sink.
Base cabinet size
To determine the maximum sink size for your base cabinet, measure the interior of your cabinet and subtract two to three inches from each dimension. A 36″ base cabinet can handle a 33″ sink at most; a 30″ cabinet should be fitted with a sink no larger than 27″ wide.
A garment marked as a size 12, for example, would now fit like a size 10 (in other words, vanity sizing).
Vanity sizing is defined as the practice of labeling clothing with a size smaller than the actual cut of the items. In other words, your size 34 might actually be a size 36, or larger. This is done to make the customer feel better about themselves and to make them buy more clothing.
According to the National Kitchen & Bath Association, “The standard depth is 21” to the front of the box plus the thickness of doors and drawers. Some vanity cabinets used in small baths will be as little as 18” or 16”.” Always confirm that the vanity you choose is deep or shallow enough to work for your bathroom.
The standard vanity size for single vanities is between 36 and 48 inches wide, making them a fantastic option for guest bathrooms and powder rooms. When you have an especially small bathroom design, there are even wall-mounted vanities designed to free up valuable floor space.
Typically a custom vanity costs about twice as much as a prefab vanity because there are more subcontractors involved in making and putting the vanity together.
Instead, think about the overall size of your new bathroom and plan to install a vanity that will fit comfortably within it. Having a vanity that's too large in a smaller bathroom will make the entire room less functional and comfortable.
A standard bathroom cabinet overhang is about 1 to 1 1/2-inches. This slight overhang is attractive and helps protect the cabinets below the counters from spills. However, some homeowners desire a larger or smaller overhang due to the benefits each can offer.
If the top is on a free standing vanity (no walls on either side) the top should be 2” LONGER (B) than the vanity to allow for 1” overhang on each side.
Installing a new bathroom vanity top ranges from $200 to $1,000, or an average of $100 to $150 per hour, depending on the size, the number of sinks, and material. To complete the installation of your new vanity countertop, you will need to hook up the bathroom sink and faucet.