What are the actual dimension of a Lego Duplo Brick

April 29, 2022 1:32 PM

I want to design my own Lego Duplo Bricks and looked online for their dimensions, but wanted to check the actual bricks. So I bought nice calipers from Mitutoyo, but my measurements do not match those of others. As it is my first time measuring something with calipers I wanted to ask you, what dimensions does your 2x4 lego duplo brick have? I got 31.75 mm for width, 19.25 for height and 63.60 mm for length. As the dimesions of normal Lego bricks are better documented I'll get some tomorrow to measure. Maybe someone can tell me his measurements of those too?
posted by SweetLiesOfBokonon to Science & Nature (5 answers total)

People doing 3d modelling of LEGO usually use the LDU unit, which is 0.4mm. LDUs are used in LDraw, the open CAD standard for LEGO. A standard brick height is 24LDU, or 9.6mm. DUPLO is typically 2x size, so that would be 19.2mm high. Standard brick width is 20LDU, or 8mm (that's a 1x1 standard LEGO block). 2x4 DUPLO is 4x by 8x this measurement, or 32mm x 64mm. However, 31.8 x 63.6 is the size in the parametric model I've used in Fusion360, so that might be closer to reality.
posted by pipeski at 1:51 PM on April 29, 2022

Response by poster: @pipeski: I'm also using 360 and parametric modelling. Could you tell me what other parameters you have?
Do you use this model to print bricks or is it just for simulation?
posted by SweetLiesOfBokonon at 2:03 PM on April 29, 2022

what is your measurement technique?
posted by Dr. Twist at 2:24 PM on April 29, 2022

Best answer: I only have dial calipers in silly units, but I measured and got 2.505" l * 1.247" w * 0.754" h = 63.63 * 31.67 * 19.15mm
posted by supercres at 3:10 PM on April 29, 2022

You may have qualified success 3D printing Duplo-compatible (and especially Lego-compatible) bricks. The tolerances in the bricks are absurdly small to ensure positive engagement. If you have access to an industrial printer you might make bricks that work.
posted by scruss at 8:40 AM on April 30, 2022