Bead Calculator
Enter the size of your design to see how many beads, bags and pegboards you need and how big it will be — or enter the beads you have to find the largest design they allow. Everything is calculated in your browser.
Large square boards are 29 × 29
100 = every spot has a bead
For lost and misshapen beads
Lower it for designs with empty areas
One colour per line: a name, then a comma, then how many beads.
🔒 Runs in your browser — nothing you enter or open is uploaded or stored. Last reviewed: October 2026.
How to use the Bead Calculator
- Open the tab you need: Beads for a size, Size from my beads or Shopping list.
- For a size, enter the width and height in beads, choose the bead size (mini, midi or maxi) and the board size in pegs. Leave “How full” at 100 unless the design has empty areas.
- Set the spare percentage and how many beads come in a bag. The results update as you type.
- To find the largest design from the beads you own, enter the bead count and read the table of shapes — square, 4 : 3, 3 : 2, 16 : 9 and portrait versions.
- For a shopping list, open a project saved in the pattern generator or maker, or type one colour per line with its bead count, and copy the result.
The formulas
Everything here is plain arithmetic, so you can check it by hand:
- Beads in the design = width × height × fill ÷ 100.
- Beads to buy = beads in the design × (1 + spare ÷ 100), rounded up.
- Bags = beads to buy ÷ beads per bag, rounded up.
- Finished size = number of beads × bead width (2.6, 5 or 10 mm).
- Boards = (width ÷ board size, rounded up) × (height ÷ board size, rounded up).
Worked example: a 58 × 40 design at 100% fill needs 2,320 beads. With 10% spare that is 2,552, so three bags of 1,000. At 5 mm per bead it measures 29 × 20 cm, and on 29 × 29 boards it needs 58 ÷ 29 = 2 and 40 ÷ 29 = 1.4, rounded up to 2, so 2 × 2 = 4 boards.
Bead sizes and finished size
Fuse beads come in three common nominal sizes. The finished size is the grid size multiplied by the bead width, so a 29 × 29 design changes a lot with the bead size.
| Size | Bead width | Beads per 10 cm | 29 × 29 design |
|---|---|---|---|
| Mini | 2.6 mm | 38 | 7.5 × 7.5 cm |
| Midi (most common) | 5 mm | 20 | 14.5 × 14.5 cm |
| Maxi / jumbo | 10 mm | 10 | 29 × 29 cm |
Brands differ by a fraction of a millimetre, and ironing flattens and fuses beads slightly, so treat the finished size as a close estimate. Read the guide to bead sizes and pegboards for more.
How many beads are in a bag?
There is no standard. Packs range from a few hundred beads in a small tub to many thousands in a large mixed tub, and single-colour refills are sold in different counts. Check the label and type the number into “Beads per bag”. The default of 1,000 is only a convenient round number.
Mixed tubs rarely contain the colours in the proportions a pattern needs. Use the Shopping list tab to see how many beads of each colour to buy, and round each colour up to the pack sizes your shop actually sells.
The largest design from the beads you have
Enter how many beads you own and how full the design will be. The calculator finds the largest whole-number grid in several shapes whose bead count does not exceed your total. For example, 5,000 beads at 100% fill make a square of 70 × 70 (4,900 beads) or a 4 : 3 rectangle of 81 × 61 (4,941 beads). Lower the fill if your design has empty areas: at 60% fill the same beads stretch to a square of 91 × 91.
Why keep spare beads?
Beads get lost, land with the hole facing the wrong way, or turn out slightly misshapen. A margin of about 10% per colour is a common rule of thumb; use more for tiny details in rare colours and less for large single-colour areas. Spare beads also let you fix mistakes found while ironing.
Frequently asked questions
Does the finished size include the pegboard?
No. It is the bead grid only: the number of beads in each direction times the bead width. A frame or backing adds to it, and a pegboard’s border is not counted.
Do beads shrink when ironed?
They fuse and flatten, and the piece may become a little smaller or less precisely square depending on how long and how hot you iron. The calculator uses the nominal bead width.
What does “How full?” mean?
It is the share of grid squares that get a bead. A solid rectangle is 100%. A heart on a larger background grid might be 50–60%. Lower values reduce the beads to buy.
Which bead sizes are supported?
Mini (2.6 mm), midi (5 mm) and maxi (10 mm). If your beads differ slightly, the finished size will differ by the same proportion.
How do I get a colour list from my pattern?
Press “Save project (.json)” in the bead pattern generator or maker, then open that file on the Shopping list tab.
Is anything stored or uploaded?
No. The calculator runs in your browser. Opened files are read locally and not sent anywhere.