Methods & worked examples
Drawer Divider Spacing Calculator — Methods & worked examples
How it works
For n compartments, use d = n − 1 dividers. Clear width g = (internal width W − d × divider thickness t) ÷ n. For divider i: left edge = i × g + (i − 1) × t; centerline = left edge + t ÷ 2; right edge = left edge + t.
Worked examples
An internal width of 500 mm divided into 4 compartments with 6 mm dividers needs 3 boards. Subtract 18 mm, then divide 482 mm by 4: each clear compartment is 120.5 mm. Measured from the inner left side at 0 mm, divider positions (left, center, right) are (120.5, 123.5, 126.5), (247, 250, 253) and (373.5, 376.5, 379.5) mm.
Scope & limitations
Every position uses full precision from one common origin. Do not add rounded compartment widths repeatedly, which accumulates error. Measure actual internal width and board thickness. The range is 1–500 parallel compartments. Extra frames, grooves, glue joints and machining allowances are separate. This is a storage-layout calculator, not structural, load-bearing, railing-code or machinery advice.
Method sources
Our original explanations and calculators use the methods above. This site is not affiliated with the cited brands or organizations.