Half Double Crochet: Repeat, Multiple and How to Work It
Half double crochet splits the difference between single crochet and double crochet almost exactly — yarn over before inserting the hook (unlike single crochet), then pull through all three loops at once in a single motion (unlike double crochet's two separate pull-throughs). The result is a stitch genuinely between its two neighbors in height, density, and speed.
No fixed multiple, but a real turning-chain quirk
Like single and double crochet, half double crochet works over any foundation count — no repeat multiple to satisfy. Its turning chain is where it gets genuinely idiosyncratic: some patterns count the turning chain-2 as the first stitch of the row, others don't, and unlike single or double crochet's more consistent conventions, half double crochet's turning-chain rule varies enough between pattern designers that it's worth checking explicitly on any specific pattern rather than assuming.
Where it sits structurally
Half double crochet's stitch height sits literally between its two neighbors — taller than single crochet, shorter than double crochet — which is exactly why swatching it directly matters more than guessing at its behavior from either neighbor. It's also, honestly, the stitch this site's own gauge-based estimate is least certain about: no reliably-sourced real project could be found to calibrate it against directly (the full search is documented on the methodology page), so its yarn-use constant splits the difference between its two neighbors' own confirmed figures rather than standing on independently-sourced ground of its own. The Yarn Quantity Estimator still treats it as its own stitch pattern rather than a silent average, but the swatch-weighing mode is the most trustworthy path for this particular stitch precisely because its in-between height makes it the easiest of the three to misjudge by eye — and, for half double crochet specifically, the one with the least direct evidence behind the gauge-model shortcut.
Why it's underused relative to its neighbors
Half double crochet doesn't get nearly the pattern support single crochet and double crochet do, despite offering a genuinely useful middle ground — a fabric with more drape and speed than single crochet, but more body and structure than double crochet. Part of the reason is the turning-chain ambiguity above: designers who want maximum clarity often default to single or double crochet specifically to avoid having to spell out a turning-chain convention that isn't as universally agreed upon.
Where it's used
Garments wanting more drape than single crochet but more structure than double crochet — cardigans, blankets, and hats where a mid-density fabric suits the design better than either extreme. It's also a common amigurumi alternative to single crochet when a slightly faster-working, marginally more open stitch is acceptable.
Common mistakes with half double crochet
Miscounting the turning chain as a stitch when the pattern doesn't intend it to count, or vice versa — this is genuinely the most common half double crochet error, and it compounds across rows if not caught immediately. Always check a specific pattern's stated convention rather than assuming.
Confusing it with double crochet's motion. The single-pull-through-all-loops step is what distinguishes half double crochet from double crochet's two separate pull-throughs — conflating the two produces an uneven, inconsistent row.
FAQ
Is half double crochet's abbreviation "hdc" universal across US and UK terminology? The abbreviation itself is common in both, but the stitch it refers to differs — UK "half treble" is the equivalent of US "half double crochet," part of the broader one-step offset between the two naming systems.
Does half double crochet drape better than single crochet? Yes, generally — its taller, more open structure gives noticeably more drape than single crochet's tight, dense fabric, though it's still firmer than double crochet at a comparable gauge.