LEGO Brick Dimensions and Measurements

The LEGO bricks are precisely designed to fit perfectly together. There is a 0.2mm gap between bricks next to each other. The gap between two bricks stacked on top of each depends on how careful to pressed them down. Of course there are several websites that show you the exact measurements, but some of them were a bit confusing or even broken.

LEGO 2×4 Brick (3001)

I enjoy working in 3D so I used Fusion 360 to create this technical drawing of the LEGO Brick. You can download the model over at GrabCAD and the PDF file from here.

lego-2×4-brick-dimensions-measurements-3001

LEGO 2×4 Plate (3020)

This plate is 1/3 of the height of a normal brick. You can download the model at GrabCAD and the the PDF file from here.

lego-2×4-plate-dimensions-measurements-3020

LEGO 1×4 Technic Brick (3701)

The technic bricks have a hole in the side for pin connectors or axles to go through. I had to cut open a brick to get the exact design of the inside tubes right. The model is available at GrabCAD and the PDF file from here.

lego-1×4-technic-brick-dimensions-measurements-3701

37 thoughts on “LEGO Brick Dimensions and Measurements”

  1. Hi. By inspecting the Plate vs the Brick, it looks like the walls are thicker. Is it possible, that the 0.6×0.2 elevations create the same thickness, so the walls at the plates are 1.4mm?

  2. The walls of the technic brick are certainly thicker (1.4mm). I confirmed this by measuring them myself. The walls of the 2×4 brick and 2×4 plate seem to be identical: 1.2mm. I am not sure what you mean with the 0..6×0.2 elevation.

  3. Please do more parts like this. I enjoy using inventor and making my own creations. A bit difficult measuring it myself. What you have done so far is very helpful. Thanks

  4. Thank you for these lego parts they really helped me with my school work. Can you please make more it would really be appreciated. Thank you very much .

  5. Everybody says that the hight is 0.96 cm. But it’s not. I stacked 200 bricks and measured the hight and got 191.2 cm (if you multiply 0.96 by 200 you get 192 cm). So the hight is more like 0.956 cm.

    You might say that’s just 0.04 mm difference. But when you stack 200 bricks that difference sums up to almost a centimeter (0.8 cm)

  6. In reference to the wall thickness question – It varies! The variation is quite simple, and not related to regular vs Technic bricks. As far as I can tell, plates and 1xn bricks have a wall thickness of 1.5 mm, as in your Technic brick drawing (not quite the 1.6 advertised in other forums). For mxn bricks (where m>1 and n > 1) the wall thickness is 1.2 mm (as you have shown), and the missing space is made up by the little nubs, which you show.

  7. A note on the horizontal dimensions. I was bothered by the 15.8*31.8 rather than 16*32, so I decided to do some tests. I believe there is definitely a allowance for play, as implied in these drawings. None of my bricks are exactly integer width and length. I measured 24 different bricks and plates. I believe the linear dimensions for width and height are exactly 8.00 mm * number of studs – 0.2 mm. When I apply this formula across my 48 measurements (24*2) I get a standard distribution of 0.016 mm. It cleanly explains 15.8 and 31.8 as well as the fact that the corner stud center is 3.9 mm and not an even 4.0 which you would expect given stud separations of 8.0

  8. Thank you! This helped a lot. I just have one question. Are the measurement in mm?

  9. Extraordinarily helpful. Thank you so much for your time and effort!

  10. Thank you Christoph for your work. :-) I work in a company that needs small cups [1] for electronic components and uses the same presses of the Arburg company [2] for production as Lego. I train apprentices for electrical engineering there. Therefore, I know that the pressing tools are slightly conical in shape so that the workpieces release well from them. Also, slightly conical shapes are good when it comes to clamping mechanically. Similar to a funnel, the studs are then inserted at progressively closer spacings. Or the studs become thicker. So here’s the question: have you checked to see if the studs or other parts are the same thickness everywhere?

    I myself do not own any Lego bricks since my childhood. However, I am thinking of using them to build 3D-mathematic-geometric models for lessons, for which I would have to glue neodymium magnets into the bricks.

    [1] examples: https://commons.wikimedia.org/wiki/File:Wiki-Folkos-P1090317-1.jpg
    [2] https://en.wikipedia.org/wiki/Arburg

  11. Hi, there is a small but important and extremely useful deviation of the Lego bricks from your drawing. I would never have noticed it if I hadn’t compared a Lego 2×4 brick with a competing product. The latter comes from Mattel, an American company with decades of injection molding experience. Accordingly, the bricks are of good quality. The deviations and shades of colors as well as unevenness and gaps between the bricks, which all is known from many competing products, are just as absent here as they are with Lego. One disadvantage is that they are more difficult to put together. If you’re used to Lego, it feels like they resist threading.

    On the other hand, the clamping force of the Mattel (M) bricks to each other is stronger than that of Lego (L). I like this, but it is rather less suitable for toddlers when they want to separate them. If I put a M brick from the top onto a L brick, the clamping force is strong, as with M. If I put the M brick from the bottom into the L brick, the clamping force is weaker, as with L. One reason is the thicker outer wall with M (1.5mm) than with L (1.2mm). Instead of the thicker outer wall, L has 0.3mm thick ribs/nubs that press against the studs. But unlike in your drawing, these do not start at the bottom of the brick, but about 0.2mm above it.

    According to the drawing, the center of the studs is 3.9mm from the outer wall. If you subtract its thickness of 1.2mm, you are left with a distance of 2.7mm from the inner wall. However, the radius of a stud is only 4.8/2= 2.4mm. It therefore does not reach the inner wall, so that no clamping takes place there. As a result, the studs of the lower brick “fall” 0.2mm deep without pressure into the opening of the upper brick up to the beginning ribs. If you press further, the studs will be clamped by the ribs. Threading into an L-brick is therefore much easier than into M-brick. Without the ribs nothing would remain stuck in the L-brick.

    In summary, these 0.2 mm shorter ribs than the Lego bricks’ height act like a funnel and make a crucial difference in assembly, especially with toddlers’ hands that are not yet so skilled. I would not have believed the big impact of this tiny cause if my young testers and I had not experienced the difference with the Mattel brick.

  12. A Legobrick single module builds 191mm/24 according to LEGO’s own dimmension drawing that came with the big car chassi set in 1977.
    On that drawing the bumper width is dimmensioned to 191mm which is 24 modules in width. The total length of the car is 526 mm according to LEGOS drawing. Axle distance is 301 mm. Ground clearance 30 mm. Wheel diameter 80mm, distance in between front and rear wheel is 221 mm. Width of tyre is 24 mm, rim diameter is 43 mm.

  13. The ribs came when 2×3&4 got cross-members (>4 already have, & 2×2 never cross-members).

  14. Loved the beautiful drawings and the crisp clear numbers.
    But what are the numbers?
    Millimetres?
    Centimetres?
    Metres?
    Kilometres?
    Inches?
    Feet?
    Yards?
    Fathoms?
    Furlongs?
    Miles?
    Never seen a technical drawing before that doesn’t identify the basic unit!!!

  15. Thanks so much for this! I’m using it in a college-level Production and Operations Management class today to teach the complexity of measurement in quality control. I wonder if you’ve done any work or found anything about the specs, +/- tolerance of any of these measurements?
    My task for my students is to have them measure off-brand blocks that “work with leading brands – read Lego(r)” and answer whether or not these are actually the same size as real Legos(r).
    – Dr. Jones

  16. You will need very precise measurement tools. I doubt that you students will be able to make any statistically significant observations of differences between brants. They have become just as good. But great idea! Good luck!

  17. Hi, in 2*4 plate distance between 2 studs is 8+4.8=12.8 mm (from outer).( there is no ribs. )
    However the net distance below lego is 15.8-(1.2+1.2)= 13.4 mm which is bigger. How can it be clamps?

  18. Thank you so much. I used these measurements to 3D print some blocks, and they came out great.

  19. Regarding the difference in wall thickness of regular vs Technic, I believe the wall thickness of the Technic is more in line with the original Lego blocks.

    Some time in the late 80’s / early 90’s, they thinned the walls down , but had to add the ribs in order to catch the circular peg from the brick below at the contact point.

    I imagine it saved a lot of plastic over millions of Legos, but sometimes the newer Legos would crack.

    :(

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