Free planning tool
Perler Bead Size & Calculator
Enter a pattern’s width, height, fill rate, and spare allowance. The calculator returns the full-grid capacity, estimated bead count, quantity to prepare, approximate finished dimensions, and number of 29×29 pegboards.
Live estimate
29 × 29 pattern
5 mm pitch · 29 × 29 pegboards
- Theoretical full grid
- 841
- Estimated pattern count
- 715
- Recommended to prepare
- 787
- Approx. finished size
- 14.5 × 14.5 cm
- 29 × 29 boards
- 1
beads at 100% fill
85% occupied cells
10% spare included
before fusing
1 across × 1 down
Quick reference
Common square pattern sizes
Counts below assume every cell is filled. “Prepare” adds a 10% spare allowance. Size uses an approximate 5 mm bead pitch.
| Grid | Maximum beads | Prepare +10% | Approx. size | 29×29 boards |
|---|---|---|---|---|
| 10 × 10 | 100 | 111 | 5 × 5 cm | 1 (1 × 1) |
| 20 × 20 | 400 | 441 | 10 × 10 cm | 1 (1 × 1) |
| 29 × 29 | 841 | 926 | 14.5 × 14.5 cm | 1 (1 × 1) |
| 30 × 30 | 900 | 991 | 15 × 15 cm | 4 (2 × 2) |
| 40 × 40 | 1,600 | 1,761 | 20 × 20 cm | 4 (2 × 2) |
| 50 × 50 | 2,500 | 2,750 | 25 × 25 cm | 4 (2 × 2) |
| 58 × 58 | 3,364 | 3,701 | 29 × 29 cm | 4 (2 × 2) |
| 75 × 75 | 5,625 | 6,188 | 37.5 × 37.5 cm | 9 (3 × 3) |
| 100 × 100 | 10,000 | 11,000 | 50 × 50 cm | 16 (4 × 4) |
Calculation method
Simple formulas you can verify
full grid = width × height
estimated beads = full grid × fill rate
prepare = estimated beads × (1 + spare rate)
size in cm ≈ bead count per side × 0.5
boards = ceil(width ÷ 29) × ceil(height ÷ 29)
The size estimate uses a 5 mm planning pitch. Perler’s product page lists an individual bead at 5.07 mm high by 4.77 mm wide, so this calculator gives a useful project estimate rather than a manufacturing measurement. Check a test strip when exact finished dimensions matter.
Board counts assume connectable 29×29 square boards. Perler’s large clear square boards connect for multi-board projects; confirm the peg count on your own board before buying supplies. The bead dimensions are sourced from Perler’s 1,000-bead product specification.
From estimate to exact list
Generate the pattern and count every color.
Calculator FAQ
Common size and count questions
How many beads fit on a 29×29 Perler board?
A fully occupied 29×29 grid contains 841 cells, so it uses at most 841 beads. A design with 80% fill uses about 673 beads before adding spares.
How large is a 29×29 Perler bead pattern?
At an approximate 5 mm pitch, a 29×29 pattern spans about 14.5 × 14.5 cm before fusing. The physical board can be slightly larger than the bead area.
How does fill rate change the bead count?
Fill rate estimates how many grid cells contain beads. Multiply width by height, then multiply by the fill rate as a decimal. A 50×50 grid at 70% fill is about 1,750 beads.
How many extra Perler beads should I prepare?
Ten percent is a practical default for sorting mistakes, damaged beads, and small edits. Increase it for large projects, color substitutions, or uncertain inventory.
Why can the fused size differ from the estimate?
The calculator uses a 5 mm planning pitch. Bead dimensions, peg spacing, fusing pressure, heat, and cooling can change the finished measurement slightly.