Crochet Circle Calculator
Get round-by-round stitch counts and written instructions for a flat crochet circle.
How to Use
- Enter your target finished diameter and stitch gauge.
- Choose a 6-stitch start for a tighter, less visible center hole, or an 8-stitch start for a flatter, more even center.
- The calculator generates round-by-round instructions following the standard flat circle formula.
The Flat Circle Formula
A mathematically flat crochet circle increases by the starting stitch count every round. Start with 6 stitches → add 6 each round (round 1: 6, round 2: 12, round 3: 18, etc.). Start with 8 → add 8 each round.
In practice, stitches are spaced evenly around the round with increases distributed to avoid a spiral. Increase placement shifts each round to keep the circle truly flat.
Common uses: potholders, coasters, bag bases, hat brims, appliqués, mandalas.
Results are estimates. Actual finished diameter varies by yarn weight, hook size, and tension.
About this Crochet Circle Calculator
A flat crochet circle needs a consistent increase rate to stay flat — too few increases and it cups upward like a bowl; too many and it ruffles at the edges. The standard rate adds the same number of stitches each round as the number of stitches in the starting ring.
Why circles cup or ruffle
A circle's circumference grows faster than its increase rate can compensate for if too few stitches are added each round, causing the fabric to cup inward to accommodate the shortfall. Too many increases add more fabric than the growing circumference needs, causing the excess to ruffle outward. Matching the increase count to the round number keeps the circle flat.