Crochet Circle Calculator

How to use this single crochet planner

Measure stitches per inch on a swatch made with the same yarn, hook, and single crochet stitch. Enter your target diameter, then choose the increase rate your pattern or test circle uses. A six-stitch start is a common starting point for single crochet; eight increases per round adds more fabric and may ruffle with some yarns.

Work in continuous rounds with a stitch marker. Here, sc means single crochet in US terminology, and an increase means two single crochet stitches in one stitch. The table repeats each increase group around the round. It does not stagger increases, so aligned increases may produce visible corners.

How the estimate works

Target circumference = π × diameter. Target edge stitches = circumference × stitches per inch. Estimated rounds = target edge stitches ÷ increases per round, rounded up. Round n contains n × the starting stitch count. Between increases, work n − 2 plain stitches.

Worked example: an eight-inch circle

At four stitches per inch with six increases per round, the target edge needs π × 8 × 4 ≈ 100.53 stitches. Rounding up to a complete round gives 17 rounds and 102 edge stitches, corresponding to an estimated diameter of 8.12 inches. Round one has six stitches; round two increases in every stitch for 12; round three repeats (increase, one sc) six times for 18; round four repeats (increase, two sc) six times for 24.

Why is my circle cupping or ruffling?

Cupping can indicate too few increases for your fabric; ruffling can indicate too many. Stitch height, tension, and yarn also affect the result. This calculator uses horizontal stitch gauge only, so the estimated round count cannot guarantee a flat circle or an exact diameter. Lay the circle flat and measure as you go. Follow your pattern's increase adjustments if the fabric will not lie flat.

Does the starting count control the center hole?

The starting count controls the number of increases per round in this planner. Closing the magic ring controls the center opening. Secure the yarn tail according to your project's construction; choosing eight stitches does not by itself close the hole.

Check your measurements with the crochet gauge calculator and read the gauge swatch guide before planning a fitted project.

Use this as a single crochet planning estimate, not a substitute for a tested pattern. The table supports up to 500 rounds.