Gridfinity bin sizing guide: choosing units and heights, fitting a drawer, print settings

A Gridfinity bin is sized in 42 mm units across and 7 mm units tall, so fitting out a drawer is arithmetic: measure, divide, round down, and fill the remainder with a spacer.

Updated 27 October 2026 · 8 min read

The numbers that define a bin

Gridfinity fixes three dimensions and everything else follows. The grid pitch is 42 mm. A 1-unit bin is 41.5 mm across (42 minus a 0.5 mm clearance, 0.25 mm each side), a 2-unit bin is 83.5 mm, and in general an n-unit bin measures 42n minus 0.5 mm. The baseplate has 42 mm cells, so bins sit with a quarter-millimetre gap all round and do not bind.

Height is measured in 7 mm units. The base profile (the stepped foot that drops into the baseplate) is 4.75 mm tall and sits inside the first unit; the stacking lip on top adds 4.4 mm above the nominal height. A "3u" bin has a nominal height of 21 mm, and with the lip stands about 25.4 mm tall overall. When stacked, the lip of the lower bin nests into the base of the upper one, so stacked bins add exactly 7 mm per unit of nominal height.

Usable interior depth is roughly nominal height minus 6 mm (the floor thickness above the base profile, typically 0.8 to 1.2 mm, plus the base itself). It varies by generator, so measure your own bin before relying on it.

Baseplates are 42n mm exactly (no clearance) and come in several profiles: a thin "skeletonised" plate about 5 mm thick, a plate with magnet pockets, and weighted or screw-down plates that reach 7 mm or more. The Gridfinity explained guide covers the standard in detail; this one is about picking sizes.

Measuring the drawer

Measure the inside width, depth and height of the drawer, not the front face. Take width at the back and front, depth at left and right, since drawers are rarely square. Use the smaller of each pair. Then subtract:

• Any rail, screw head or stop that intrudes into the usable area.
• About 1 mm of play so the baseplate drops in without forcing.
• For height: measure from the drawer floor to the underside of the frame above it with the drawer open, not to the top of the drawer side. Then subtract the baseplate thickness and the stacking lip of the top bin.

Example: an IKEA Alex drawer measures 311 × 410 mm internally with 60 mm clear height in the shallow version. Subtract 1 mm each way: 310 × 409.

How many units fit

Divide each usable dimension by 42 and round down. For the Alex drawer: 310 / 42 = 7.38, so 7 units (294 mm); 409 / 42 = 9.74, so 9 units (378 mm). That is a 7 × 9 baseplate, leaving 16 mm spare across and 31 mm front to back.

Height: 60 mm clear, minus a 5 mm baseplate, minus 4.4 mm lip on the top bin, leaves 50.6 mm of nominal bin height, so 7u (49 mm) fits, 8u (56 mm) does not. With a 6u bin you keep 7.6 mm of clearance, which is comfortable; a 7u bin fits with 1.6 mm to spare, which works if the drawer slides are not sloppy.

The general formula:

• Grid units across = floor((inside width − 1) / 42)
• Grid units deep = floor((inside depth − 1) / 42)
• Max bin height units = floor((clear height − baseplate thickness − 4.4) / 7)

Printer bed size caps the baseplate pieces, not the total. A 256 mm bed prints 6 × 6 (252 mm); a 220 mm bed prints 5 × 5 (210 mm); a 180 mm bed prints 4 × 4 (168 mm). Tile the drawer with pieces of those sizes plus a remainder strip. For the 7 × 9 example on a 256 mm bed: two 6 × 6 pieces would overrun, so use 4 × 6 + 3 × 6 across the front and 4 × 3 + 3 × 3 behind, or any other tiling that sums to 7 × 9.

Dealing with the leftover space

There is almost always a gap between the grid and the drawer walls, because drawers are not sized in 42 mm multiples. Options, from most to least useful:

• Spacers. Print flat strips of the gap width and 5 mm height that sit between the baseplate and the drawer wall. They stop the whole grid sliding when the drawer is opened. Most Gridfinity generators have a spacer or "drawer fill" option that takes the remainder in millimetres.
• Centre the grid and split the gap both sides. Looks tidier, and the spacers are then equal pairs.
• Push the grid to one side and use the gap for something flat, like a ruler or a notebook.

For a 31 mm gap front-to-back, a single 31 × 294 × 5 mm spacer strip at the back takes 25 g of filament and 30 minutes. Two 15.5 mm strips front and back do the same job and let bins reach to the front.

Choosing bin sizes for what goes in them

The 42 mm pitch and 7 mm height steps suit most workshop and desk contents directly. Working sizes that people settle on:

Two rules of thumb. Keep most bins at 3u in a shallow drawer and 6u in a deep one so stacks of two line up; mixed heights look untidy and do not stack. Keep small-part bins to 1 × 1 and 1 × 2 and use dividers rather than many tiny bins, because every bin costs 0.5 mm of wall and about 1 mm of gap.

The Gridfinity generator produces bins at any whole-unit width, depth and height, with options for dividers, scoops, label tabs and magnet holes, and exports STL directly. Set the target printer bed so it warns when a baseplate or bin exceeds it. If you need a plate that spans a larger area than the bed, generate the tiles separately or split a large STL with the STL splitter along cell boundaries.

Print settings

Gridfinity parts need the base profile to be accurate and the walls to be rigid. Settings that work on a 0.4 mm nozzle:

• Layer height: 0.2 mm. The base profile has 45° chamfers and prints cleanly at 0.2; 0.28 works but the chamfers get stepped and bins sit a fraction higher.
• Walls: 2 perimeters (0.8 mm) for bins, 3 for baseplates that will be screwed down. Most generators draw bin walls at 0.95 to 1.2 mm, which is 2 to 3 lines; check in the slicer preview that there is no gap between perimeters.
• Top and bottom layers: 4 and 4 at 0.2 mm. The bin floor is thin, around 1 mm, so set bottom layers rather than relying on infill.
• Infill: 15 % for bins; anything beyond is unused because the walls are solid. Baseplates have no infill volume to speak of.
• Supports: none. Bins print upright and the base profile's 45° chamfers are self-supporting. Magnet pockets print as blind holes from the bottom; use a 0.2 mm bridge layer or the "magnet hole crush ribs" option if your generator has one.
• Material: PLA is fine in a drawer. PETG for anything near heat, or if the bins will see solvents. ABS/ASA for a hot garage; note that ASA shrinks about 0.5 % and bins may need a 0.5 % XY scale-up to fit a PLA baseplate.
• Dimensional check: print one 1 × 1 bin and one 1 × 1 baseplate first. The bin should drop in with a visible gap and not rattle more than about 0.5 mm. If it binds, calibrate horizontal expansion (Cura: Horizontal Expansion -0.05 to -0.1 mm; PrusaSlicer/Bambu: XY hole and contour compensation) rather than scaling the model.

A full worked example

Drawer: 310 × 409 × 60 mm usable. Grid: 7 × 9, max 7u. Plan: back row 1 × 1 × 3u bins for screws (7 bins), middle 1 × 2 × 3u bins for tools lying flat (14 bins in two rows), front 2 × 3 × 6u bins for bulkier items (two of them, plus a 3 × 3 × 6u). That fills 7 × 9 exactly. Spacers: 16 mm strip on one side, 31 mm strip at the back. Print order: baseplate tiles first (4 × 6, 3 × 6, 4 × 3, 3 × 3), check the fit in the drawer, then bins in batches of four to six 1 × 1s per plate. Total filament roughly 900 g, mostly PLA, over about 40 hours of printing on a 256 mm bed.

FAQ

How wide is a 1-unit Gridfinity bin?

41.5 mm. The grid pitch is 42 mm and each bin is 0.5 mm smaller for clearance, so an n-unit bin is 42n minus 0.5 mm.

How tall is a 3u Gridfinity bin?

21 mm nominal, about 25.4 mm overall including the stacking lip. Each additional unit adds 7 mm.

How do I work out how many bins fit my drawer?

Measure the inside width and depth, subtract 1 mm, divide by 42 and round down for each. Measure clear height, subtract the baseplate thickness and 4.4 mm for the top lip, divide by 7 and round down for the maximum bin height.

What do I do with the gap at the edge of the drawer?

Print spacer strips of the gap width to hold the baseplate in place. Most generators have a spacer option that takes the remainder in millimetres.

What print settings should I use for Gridfinity bins?

0.2 mm layers, 2 perimeters, 4 bottom layers, 15 % infill, no supports, PLA or PETG. Print one bin and one baseplate cell first to check the fit before committing to a drawer's worth.