30 Block Circle Generator
At 30 blocks across you are building an arena rather than a room. The curve is smooth enough that small mistakes stand out, so it is worth marking the widest rows before placing anything else.
Controls
Circle Generator
30 x 30 · 100 blocks
Build summary
- Diameter
- 30
- Radius
- 15.0
- Total blocks
- 100
- Rows used
- 30
Symmetry check: mirrors left to right and mirrors top to bottom.
Ring built between the outer edge and an inner edge 1 block inside it.
Row-by-row instructions
- Row 1:skip 11 spaces, place 8 blocks
- Row 2:skip 8 spaces, place 3 blocks, leave 8 spaces, place 3 blocks
- Row 3:skip 7 spaces, place 2 blocks, leave 12 spaces, place 2 blocks
- Row 4:skip 5 spaces, place 2 blocks, leave 16 spaces, place 2 blocks
- Row 5:skip 4 spaces, place 2 blocks, leave 18 spaces, place 2 blocks
- Row 6:skip 3 spaces, place 2 blocks, leave 20 spaces, place 2 blocks
- Row 7:skip 3 spaces, place 1 block, leave 22 spaces, place 1 block
- Row 8:skip 2 spaces, place 1 block, leave 24 spaces, place 1 block
- Row 9:skip 1 space, place 2 blocks, leave 24 spaces, place 2 blocks
- Row 10:skip 1 space, place 1 block, leave 26 spaces, place 1 block
- Row 11:skip 1 space, place 1 block, leave 26 spaces, place 1 block
- Row 12:place 1 block, leave 28 spaces, place 1 block
- Row 13:place 1 block, leave 28 spaces, place 1 block
- Row 14:place 1 block, leave 28 spaces, place 1 block
- Row 15:place 1 block, leave 28 spaces, place 1 block
- Row 16:place 1 block, leave 28 spaces, place 1 block
- Row 17:place 1 block, leave 28 spaces, place 1 block
- Row 18:place 1 block, leave 28 spaces, place 1 block
- Row 19:place 1 block, leave 28 spaces, place 1 block
- Row 20:skip 1 space, place 1 block, leave 26 spaces, place 1 block
- Row 21:skip 1 space, place 1 block, leave 26 spaces, place 1 block
- Row 22:skip 1 space, place 2 blocks, leave 24 spaces, place 2 blocks
- Row 23:skip 2 spaces, place 1 block, leave 24 spaces, place 1 block
- Row 24:skip 3 spaces, place 1 block, leave 22 spaces, place 1 block
- Row 25:skip 3 spaces, place 2 blocks, leave 20 spaces, place 2 blocks
- Row 26:skip 4 spaces, place 2 blocks, leave 18 spaces, place 2 blocks
- Row 27:skip 5 spaces, place 2 blocks, leave 16 spaces, place 2 blocks
- Row 28:skip 7 spaces, place 2 blocks, leave 12 spaces, place 2 blocks
- Row 29:skip 8 spaces, place 3 blocks, leave 8 spaces, place 3 blocks
- Row 30:skip 11 spaces, place 8 blocks
Block counts for a 30 block circle
- Hollow outline (1 block wall): 100 blocks
- Filled disc: 716 blocks
- Widest row: 30 blocks
- Center: a 2x2 center square
Building advice for this size
- Lay out the 2x2 center, then run four straight guide lines 15 blocks long to the outer edge in each direction.
- Work one quadrant at a time and mirror it. Mirror mode in the controls shows exactly one quadrant to copy.
- A 30 wide circle needs about one and a half stacks of blocks for a 1 thick ring, or five to six stacks for a 3 thick wall.
- Check the shape from the air every few rows — errors are much easier to see from above than from inside the ring.
Other circle sizes
Smaller: 25 block circle. Larger: 40 block circle. Or open the full circle generator for any diameter up to 256.
Frequently asked questions
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