Block Circle Generator for Minecraft
A block circle is a grid approximation of a circle, not a circle. Because a square grid cannot hold a curve, a generator has to decide which cells count as being inside the shape, and the choice of rule is what makes one generator's pattern differ from another's. This one keeps a cell when the centre of that cell falls inside the requested circle or exactly on its edge, which produces a pattern that is exactly symmetric left to right and top to bottom at every size. The outline is the same shape with its interior removed. The tool is independent and is not affiliated with Mojang Studios or Microsoft.
Pick a diameter in blocks, choose an outline or a filled circle, and read the pattern straight off the grid. The block count comes from the grid you are looking at, and the rule that decides which cells become blocks is written out below rather than left to guesswork.
Quick Answer
Enter a diameter in whole blocks and the grid is drawn from one rule: a cell becomes a block when its centre falls inside a circle of that size. A 10-block circle is 28 blocks as an outline and 80 filled.
Not an official Minecraft product. Not approved by or associated with Mojang or Microsoft. See the Minecraft Usage Guidelines.
Size given as
Whole blocks, 1 to 128. · e.g. 10
Style
Copies the pattern as # for a block and . for a gap, one character per block, so the rows line up in any monospaced editor.
10 blocks across, 10 blocks tall.
Blocks in the outline
28
10 x 10 grid, 10 blocks in diameter
A grid approximation, not a true circle. Every cell whose centre falls inside the circle is a block, which is what gives the pattern its exact left-to-right and top-to-bottom symmetry.
Examples
Diameter 5, outline
12 blocks in a 5 x 5 grid
Diameter 10, outline
28 blocks in a 10 x 10 grid
Diameter 10, filled
80 blocks in a 10 x 10 grid
Diameter 25, outline
68 blocks in a 25 x 25 grid
How it works
Formula · block when (x + 0.5 - d/2)² + (y + 0.5 - d/2)² ≤ (d/2)²
There is one rule, and it is applied the same way at every size. No lookup tables, no hand-tuned exceptions for particular diameters.
A cell is a block when
(x + 0.5 − d/2)² + (y + 0.5 − d/2)² ≤ (d/2)²
d is the diameter in blocks, and x and y number the cells from zero.
- the grid is d wide and d tall
- the circle sits at the middle of it, at (d/2, d/2)
- each cell is judged by its own centre, at (x + 0.5, y + 0.5)
- centre inside the circle, or exactly on it, means a block
Symmetry is not applied afterwards, it falls out of the arithmetic. Column x sits (x + 0.5 − d/2) from the middle and the column mirroring it sits exactly the same distance the other way, so squaring the two gives the same number. The rows work identically. Every pattern this page draws is therefore symmetric left to right and top to bottom, at every size.
Outline or filled
The filled circle is every cell the rule accepts. The outline is that shape with its interior taken out: a block survives unless all four of its edge-sharing neighbours are blocks too. A block on the edge of the grid is missing a neighbour, so it always stays.
Building the outline out of the filled shape rather than measuring it separately means the two can never disagree. The outline is always a subset of the filled circle, always sits in the same square, and always inherits the same symmetry. It also gives you the useful pair of numbers: a 25-block circle is 68 blocks as an outline and 489 filled, so the inside is 421 blocks of whatever you are filling it with.
Odd and even sizes centre differently
With an odd diameter the middle of the circle lands in the middle of a block, so there is one centre block, one centre row and one centre column. Handy: you can stand on the middle and count outwards in four directions.
With an even diameter the middle lands on the seam between two blocks. There is no centre block, and the centre row and column are two wide. A 10-block circle and an 11-block circle are therefore not the same shape with one extra ring; they are laid out differently from the start. Decide which you want before you place anything, because converting between them later means rebuilding.
How close is it to a real circle?
Close, and closer as the circle gets bigger. The area of a true circle 25 blocks across is about 490.9 square blocks and the filled pattern uses 489 blocks, under half a percent out. At 10 across the true area is 78.5 and the pattern uses 80. The small sizes are where a grid has least room to work with, which is also where the shapes look least round.
For the continuous version of the same maths, the circle calculator gives area and circumference from a radius or diameter.
About the name
This is an independent tool for planning block circles in Minecraft. It is not made by, endorsed by or affiliated with Mojang Studios or Microsoft, and Minecraft is their trademark. The geometry here is ordinary grid geometry and works just as well for cross stitch, pixel art, tiling or anything else laid out on squares.
Source
This page draws its naming and disclaimer from Minecraft's published usage guidelines, which informed the naming and disclaimer used on this page, not a claim that Mojang or Microsoft signed off on this page or its wording. Verified 15 August 2026.
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Frequently asked questions
No, and no block circle is. A circle is a continuous curve and a grid of blocks cannot hold one. What you get is an approximation: the set of grid cells whose centres fall inside a circle of the size you asked for. That rule is stated on this page rather than hidden, because a different rule gives a different pattern and both would look plausible.
Because at that size the rule and the grid disagree about what a circle looks like. A radius of 1.5 reaches 1.5 blocks from the middle, and the corner cell centres sit only about 1.41 blocks away, so they are inside and they get filled. Very small circles are all corner, and every generator has to pick something. Below about five blocks across, look at the pattern rather than trusting the label.
An odd diameter puts one block exactly in the middle, so there is a single centre column and a single centre row to line up with. An even diameter has no middle block: the centre of the circle falls on the seam between two blocks, so the pattern has a two-wide centre instead. Neither is better, but they build differently, and it is worth choosing before you place the first block.
It is the filled circle with its inside removed. A block stays in the outline unless all four of its edge neighbours, up, down, left and right, are also blocks. Deriving it from the filled shape rather than from a second measurement is what guarantees the outline is always exactly one block thick where it needs to be, sits inside the same square, and shares the filled shape's symmetry.
Because that is where the picture stops being useful, not where the maths stops working. At 128 across the grid is over sixteen thousand cells and each one is a couple of pixels wide on a phone. The rule itself has no upper limit.
No. This is an independent geometry tool for planning block circles, with no connection to Mojang Studios or Microsoft. Minecraft is their trademark and is named here only to say what the tool is for.
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