How many blocks is a 20 block circle?

A hollow 20 block circle uses 60 blocks for the outline. Filled in as a disc it uses 316 blocks.

Which circle size looks the roundest?

From about 15 blocks upwards a circle reads as round from ground level, and by 25 to 30 it looks convincingly smooth. Sizes below 9 always look angular because there are too few blocks to describe the curve.

Why are the counts not exactly pi times the diameter?

Because a block ring is a staircase, not a smooth curve. Where the curve is nearly flat, one block covers a long stretch of it, so the block count comes out below the true circumference — and it jumps in steps rather than smoothly as the diameter grows.

Reference

Minecraft circle size chart

Every number below is produced by the same algorithm the circle generator uses, so it matches the blocks you will actually place.

4 minute read

The chart

Hollow and filled block counts for Minecraft circle diameters from 5 to 100
Diameter	Hollow ring	Filled disc	Centre
5	12	21	single block
7	16	37	single block
9	32	69	single block
10	28	80	2 x 2
11	28	97	single block
12	32	112	2 x 2
13	40	137	single block
15	40	177	single block
17	48	225	single block
19	68	293	single block
20	60	316	2 x 2
21	56	349	single block
25	68	489	single block
27	88	577	single block
30	100	716	2 x 2
33	112	861	single block
35	112	973	single block
40	140	1,264	2 x 2
45	140	1,597	single block
50	172	1,976	2 x 2
64	204	3,228	2 x 2
75	224	4,421	single block
100	304	7,860	2 x 2

How to read it

The hollow ring column is a one-block-thick outline: the number of blocks you place to draw the circle. Multiply it by your wall height to get the material for a round tower. The filled disc column is every block inside the circle, which is what a floor, a ceiling or a single sphere layer needs.

Notice that the counts step rather than grow smoothly — 10 and 11 blocks diameter can need the same or nearly the same outline count. That is the staircase effect: as the diameter grows by one, the outline sometimes gains a whole extra step in each quadrant and sometimes gains nothing.

Which sizes to use

5–9: decorative only — pillars, wellheads, small fountains. Visibly angular.
10–15: small towers and silos. The curve starts to read.
19–30: the best all-round range. Round enough to look deliberate, cheap enough to finish.
40–64: arenas, domes and large plazas. Plan the material first.
75–100: megabuild scale. A filled 100 disc is nearly 8,000 blocks per layer.

Get the blueprint

Any diameter from 1 to 256 works in the circle generator, including wall thickness and filled discs. The most-requested sizes have their own pages on popular sizes, and the block calculator turns any of these counts into stacks and shulker boxes.

Minecraft circle size chart

The chart

How to read it

Which sizes to use

Get the blueprint

Frequently asked questions

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