Measuring guide

How to measure for a divided drawer: step by step

By Dale McCoy, head of production · Technically reviewed by Tory O’Neal · Updated October 2026

For the homeowner or cabinet shop ordering a drawer box with the dividers built in. About twenty minutes, half at the cabinet and half at the counter, and you end up with the outside box size, the two divider counts and the size of every compartment, which is all the configurator asks for.

Ready to build it? The configurator prices every choice live and draws your box in 3D before you order.

Before you start

Empty the drawer and take it out: on undermount runners pull it fully open, squeeze the release levers under the front corners and lift; on side mount slides press the lever on each slide. Doors stay on their hinges unless one swings across the opening. Note where the slide gripped the box, on the side (side mount) or underneath at the back with a notch (undermount), and read the model off the label, such as Blum TANDEM 563H; the find my drawer page helps when the label is gone. The clear opening is inside the frame, stile to stile and rail to rail, on a face frame cabinet, and between the cabinet sides, floor or drawer below to stretcher above, on a frameless one. If the old box ran well on slides you are keeping, measure its outside width, depth and height instead; the plain drawer box measuring guide shows both cases.

Step 2: measure the opening height (B) and the inside depth (C)

Stand the tape on the bottom of the opening, the cabinet floor or the rail below the drawer, and read it at the underside of the rail, stretcher or counter support above; write it as B. Then lay the tape along the cabinet floor from the front edge of the cabinet, or the face of the frame, to the back panel and write the inside depth as C. On an old box, measure a side bottom to top, and the box front to back without the decorative front. The rules: the box is at most B minus 3/4 in tall, the room an undermount runner needs, and our standard heights of 3 1/4, 4 1/4, 5 1/4 and 6 1/4 in are picked at or below that number. On undermount runners the box depth is the runner length and the cabinet needs a little more than the runner: Blum asks for at least 21 15/16 in of inside depth for a 21 in TANDEM runner, so C must be at least that; on side mount slides the box depth is C minus about 1 in. Common mistake: measuring the drawer front for the height; it is taller than the box behind it. Tip: take C to the first obstruction, such as a hinge plate.

Step 4: measure the longest and widest items (E and F)

Lay everything out in groups of like things, one group per bay: forks, table knives, spoons, serving pieces. In each group, run the tape along the longest piece from tip to end of handle and write it as E, then across the widest piece, usually a spoon bowl or a spatula, and write it as F. The rule: a bay needs F plus about 1/2 in of width and E plus about 1 in of length. Typical sizes are in the Step 6 table, but patterns vary, so measure your own. Common mistake: measuring the blade and forgetting the handle. Tip: photograph the groups; kitchen drawer divider sizes lists the bay each item needs.

Step 6: pick the rows and bays and check each compartment (J, K and L)

Count your groups and write the bays across and the rows front to back as J; long things lie front to back in bays, boxes and jars sit side to side in rows. Convert to dividers, which is what the configurator counts: axial (front to back) is bays minus 1, lateral (side to side) is rows minus 1, 6 at most each; write them as K. Four bays in one row is 0 lateral and 3 axial. Then the check: clear bay width is the inside width minus 1/4 in per axial divider, divided by the bays; clear row depth is the inside depth minus 1/4 in per lateral divider, divided by the rows. Write it as L and compare with E and F for every group; 1/2 in dividers take 1/2 in each.

The rule: compartments equal (lateral + 1) x (axial + 1), up to 49, and the live 3D preview prints the count and size of each in its spec line. Common mistake: entering the number of bays as the number of dividers. Tip: if one group needs a wider bay, keep the counts, choose custom spacing and type the bays from the left in the layout notes; the divider layout planner works a mixed layout bay by bay.

Every measurement on one drawing

The letters match the worksheet below.

Turn your numbers into an order

A real top drawer: a 24 in frameless base cabinet on Blum TANDEM 563H 21 in runners from our undermount slides shop, holding the flatware from Step 6. A = 22 1/2, B = 5 and C = 23 in, so D is 4 1/4 in (5 minus 3/4), G is 22 1/8 in, H is 21 in, I is 20 7/8 x 19 3/4 in, J is 4 bays in 1 row, K is 0 lateral and 3 axial, and L is 5 1/32 x 19 3/4 in, which beats every group. A is a standard opening, so the standard product takes it in three picks, quoted as the configurator prints them.

Any other drawer, or this one on the custom product, maps like this. On side mount slides leave “Notching” on “None” and the depth comes from “Custom Depth (Inches)” and “Depth Fraction” instead of “Depth Selection”.

Keep “Drawer Side Thickness” on “5/8″ Thick Drawer Sides (Our Standard)”, which the 1 1/4 in deduction assumes. On side mount slides G becomes 21 7/16 in, H is 22 in from “Custom Depth (Inches)”, and the four bays come out about 4 7/8 in wide. The divided drawer configurator guide walks every field and price.

Measuring questions

Do I give you the cabinet opening or the box size for a divided drawer?

It depends on the product. The standard divided drawer box asks for the cabinet opening and makes the 3/8 in undermount deduction for you. The custom divided drawer box asks for the outside box size, so you deduct 13/32 in (10 mm, often written 3/8 in) for Blum style undermount runners with 5/8 in sides or 1 in for side mount slides, and we build exactly that.

What is the slide deduction for a divided drawer?

The same as for any drawer box, because the dividers sit inside it. Side mount slides need a box 1 in narrower than the opening; Blum style undermount runners with 5/8 in sides need 13/32 in (10 mm, often written 3/8 in). For another runner, follow the maker’s sheet and name the model in the configurator so we match the notch.

How tall should a divided drawer box be?

At most the opening height minus 3/4 in, and at least the tallest item plus about 1 1/2 in. That puts flatware in a 3 to 4 in box, utensils in 4 to 5 in, spice jars lying flat in 3 1/2 to 4 in and standing jars in about 6 in.

How do I measure a face frame cabinet for a divided drawer?

Measure inside the frame, stile to stile and rail to rail, not the wider carcass behind it. The box takes the same deduction from that frame opening, and the slides mount on blocking flush with the frame. Frame openings rarely land on the eight standard sizes, so a face frame cabinet usually takes the custom box.

How exact do my measurements need to be?

To the nearest 1/32 in on the opening, because we cut to the 1/32 inch and the fraction fields take 1/32 in steps. A width 1/8 in too big binds; 1/8 in too small still runs, so between marks, round the opening down. Round item sizes up to the nearest 1/4 in.

Can I send a photo of my measurements instead of using the configurator?

Yes. Fill in the worksheet, photograph it with the tape in the opening, and send both through the instant quote; we check the numbers and tell you which product and picks to order. A layout the configurator cannot draw, such as clip grooves, goes the same way.