LEGO · Size and scale
LEGO stud and scale converter.
Pick a direction, enter a length, and the page converts between real-world units and LEGO studs, bricks high and plates high, at full size or any scale you set. It uses the LDraw specification’s figures: a stud spacing of 20 LDU and 1 LDU = 0.4 mm, so 8 mm a stud. Example: a 10 ft (3,048 mm) wall built at 1:45, the scale a 40 mm minifigure gives a 1.8 m person, is 67.7 mm long: 8.5 studs wide and about 7 bricks tall.
Your numbers
Result
Working out the result.
How studs, bricks and plates are converted
The LDraw file format specification defines its own unit, the LDraw unit or LDU, for modelling bricks on a computer. It states that one brick width or depth is 20 LDU, one brick height is 24 LDU, one plate height is 8 LDU, one stud diameter is 12 LDU and one stud height is 4 LDU. It then gives a real-world approximation of 1 LDU = 0.4 mm and cautions that these are “just that: approximations.” Multiplying through gives 8 mm between stud centres, 9.6 mm for a brick, 3.2 mm for a plate, a 4.8 mm stud and a 1.6 mm stud height.
To go from a real length to studs the page divides the length in millimetres by your scale (1 for full size) and then by 8. To go the other way it multiplies studs by 8 and by the scale. Bricks high and plates high divide the same scaled length by 9.6 mm and 3.2 mm. For scale, Wikipedia says the height of a typical minifigure is 4 centimetres, and dividing a person’s height by 40 mm gives the 1:x ratio the page shows.
Worked examples with real numbers
- Full size. 6 ft is 1,828.8 mm, which is 228.6 studs at 8 mm a stud.
- Minifigure scale. A 1.8 m person against a 40 mm figure is 1:45. At that scale one stud stands for 8 × 45 = 360 mm, about 14.2 in.
- A 10 ft wall at 1:45. 3,048 mm ÷ 45 = 67.7 mm, which is 8.47 studs long or 7.06 bricks tall.
- Studs back to real size. A 32-stud-wide model at 1:45 stands for 32 × 360 mm = 11.52 m, about 37.8 ft.
Reference sizes used
| Feature | LDU | Millimetres |
|---|---|---|
| Stud spacing (brick width) | 20 | 8.0 |
| Brick height | 24 | 9.6 |
| Plate height | 8 | 3.2 |
| Stud diameter | 12 | 4.8 |
| Stud height | 4 | 1.6 |
What this calculator leaves out
These are the LDraw approximations for planning, not measurements of a particular part. Wikipedia notes that the moulds are permitted a tolerance of up to twenty micrometres, so a long row of studs can differ slightly from the sum, and printed set dimensions can differ by a millimetre or two. Fan-made tool, not affiliated with the LEGO Group.
Common mix-ups
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Often assumedA LEGO minifigure has one official scale ratio.
What the source saysWikipedia gives the height of a typical minifigure as 4 centimetres and states no ratio, so the scale depends on the person you compare it with: 1:45 for a 1.8 m person, 1:42.5 for 1.7 m. [1]
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Often assumedThe LDraw dimensions are exact measurements of real bricks.
What the source saysThe LDraw specification gives 1 LDU = 0.4 mm as a real-world approximation and cautions that these figures are “just that: approximations.” [2]
Checked against these sources on .
Frequently asked questions
How big is a LEGO stud in mm?
The LDraw specification puts the spacing between studs at 20 LDU, and with 1 LDU = 0.4 mm that is 8 mm. The stud itself is 12 LDU across (4.8 mm) and 4 LDU high (1.6 mm).
How many studs are in a foot?
A foot is 304.8 mm, which is 38.1 studs at 8 mm a stud. For a foot at minifigure scale (1:45) divide again by 45, which gives about 0.85 studs.
How tall is a LEGO brick and a plate?
The LDraw spec gives a brick height of 24 LDU (9.6 mm) and a plate height of 8 LDU (3.2 mm), so a brick is three plates tall.
What scale is a LEGO minifigure?
There is no single official ratio. Wikipedia gives a typical minifigure height of 4 centimetres, so the scale depends on the height you assign it: 1:45 for a 1.8 m person, 1:42.5 for 1.7 m. Enter a height in the form to see your ratio.
Are these exact measurements?
No. The LDraw spec itself says its real-world figures are approximations. Use them to plan a build, then test-fit a few bricks before you commit to a big one.
Can I convert a model back to real size?
Yes. Choose studs to real length, enter the stud count and the scale, and the page multiplies by 8 mm and the scale. A 32-stud model at 1:45 stands for 11.52 m.
Sources
Retrieved
- LDraw.org: file format specification, The LDraw Unit (LDU) — 20 LDU brick width/depth, 24 LDU brick height, 8 LDU plate height, 12 LDU stud diameter, 4 LDU stud height, 1 LDU = 0.4 mm approximation (read 2026-10-26)
- Wikipedia: Lego minifigure — “The height of a typical minifigure is 4 centimetres (1.6 in).” (read 2026-10-26)
- Wikipedia: Lego — moulds are permitted a tolerance of up to twenty micrometres (read 2026-10-26)
Planning figures, not manufacturing tolerances
Not affiliated with, sponsored or endorsed by the LEGO Group. LEGO is a trademark of the LEGO Group. The LDraw spec calls its real-world figures approximations. Nothing you type is sent or stored.