Clover Amour Ergonomic Crochet Hook Set
The gold standard in ergonomic crochet hooks with soft elastomer grips that eliminate hand strain.
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Flat Circle Crochet Calculator
Select your crochet stitch type (single, half double, or double crochet) and desired rounds or diameter. The calculator outputs the exact increase formula for every round, preventing cupping, ruffling, and hexagonal corners.
Crocheting a flat circle requires adhering to geometric circle proportions: with every new round, the circumference of the circle expands by approximately 2ฯr. Because taller stitches cover more radial distance per round, each stitch type requires a specific, fixed number of increases per round to stay completely flat.
The Golden Rules of Circle Increases
- Single Crochet (sc): Start with 6 stitches; add 6 increases per round.
- Half Double Crochet (hdc): Start with 8 stitches; add 8 increases per round.
- Double Crochet (dc): Start with 12 stitches; add 12 increases per round.
- Treble Crochet (tr): Start with 16 stitches; add 16 increases per round.
How to Fix Ruffling vs. Cupping
If your circle ruffles or creates waves, you have too many stitches per round (or your hook is too large). If your circle cups like a bowl, you do not have enough increases per round (or your tension is too tight). Staggering your increases on even-numbered rounds also prevents sharp hexagonal or octagonal corners from forming along the perimeter.
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Tulip Etimo Rose Luxury Crochet Hook Set
Precision Japanese engineered hooks with silky cushion grips and elegant travel case.
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Solid hardwood board with stainless steel pins to stack and block 10+ squares simultaneously.
Check on AmazonFrequently Asked Questions
Why is my crochet circle turning into a hexagon or octagon?
If you place your increases in the exact same spot in every round (e.g., always working 2 stitches into the first stitch of a repeat), the increase points form visible corners. To keep the shape circular, stagger your increases on even-numbered rounds by splitting the plain stitches.
Why does my crochet circle cup or curl up like a bowl?
Cupping means there are too few stitches to cover the expanding circumference. This happens if you miss increase points, use too few starting stitches for your stitch height, or work with tight tension. Switching to a larger hook or increasing more frequently solves cupping.
Why does my crochet circle ripple or ruffle around the edges?
Ruffling means there are too many stitches crowded into the circumference. Ensure you are adding only the recommended number of increases per round (e.g., exactly 6 for single crochet or 12 for double crochet).
How do I calculate the diameter of a crochet circle from gauge?
Measure your row gauge (rounds per 4 inches or 10 cm). Divide your total number of worked rounds by your rounds-per-inch to find the radius, then double the radius to find your circle's finished diameter.