# What are the actual dimensions of LEGO bricks, including tolerance provisions?

The answers to this question don't contain the (variable) assorted tolerance distances that are applied to all LEGO dimensions except for the peg spacing (which is the only measurement left out).

Has anyone made a diagram, or something similar to that article, with the actual, real world dimensions? I'm sure logical numbers might be interesting to some users, but others are looking for these dimensions for engineering purposes, so the logical numbers in the above article are useless to us.

There's loads of approximate answers incorrectly using the word "Exact" out there, so many that it's impossible to find the true exact answers. To be clear - it's impossible to have a height, width, or length that's an exact integer multiple of the peg spacing, because the lack of spacing would mean that bricks would fit too tightly (or not at all).

Does anyone verifiably know the actual size constants that are in use?

I've found assorted people making guesses (0.1mm spacing) and measuring their kits (reporting 19120mm for 200 bricks, or 0.04mm spacing), but I'm an engineer wanting to design something very large and complicated that needs to be LEGO-compatible, so I'm seeking the definitive mathematical answer, not a guess or measurement.

It appears that everything is measured in "Wall Units", which appears to be the one unit that is the least constant and is never as big as 1.6mm. As best I can tell, the thickness of these walls is what gets varied (by differing amounts) depending on what kind/size of object is being produced to derive the gaps necessary for working.

• Comment made by Michael Verschaeve in (now closed) duplicate of this same question explained pretty much why we don't have exact measurements - they are considered to be a trade secret. The question is also too broad since there are tens of thousands of different bricks of various shapes. Same bricks tend to be upgraded thus having several variations and geometrical properties. All of this makes it impossible to answer the question. – Alex Jan 4 at 14:26
• Welcome to Bricks @cnd. We're a community of volunteers, working to help people with their brick building questions. As such there's no compulsion for anyone to provide a specific answer. – Zhaph - Ben Duguid Jan 5 at 15:40
• @cnd Please remember to be kind and respectful to all member of this site. Editing your original question was the correct course of action. Your original question could have been reopened if the community voted to do so following your edits. Posting essentially the same question repeatedly does not help, and duplicates will continue to be closed or deleted. – jncraton Jan 5 at 15:42
• I'd like to highlight a couple of phrases from your question: "by the (variable) assorted tolerance" and "the one unit that is the least constant [...] the thickness of these walls is what gets varied (by differing amounts) depending on what". As you state, LEGO vary a number of these tolerances based on the element they are producing, so there is no one definitive answer. If there's a specific element that you do not own that you'd like the dimensions of, someone with some calipers may have it and be willing to provide a single point reference - but I doubt that would be sufficient for you. – Zhaph - Ben Duguid Jan 5 at 15:42
• Hi cnd! I took the liberty of editing your question to sound more friendly and objective, please review this version and revert my change if it conflicts with your original intent. – zovits Jan 7 at 9:10