Why Two Systems Exist and When It Matters
Both naming conventions describe the exact same stitches — they just use different words for them. The split happened in the early 1900s when American publications began renaming stitches independently from British ones. Neither system is "right" or "wrong," but mixing them up ruins your project.
You need to convert terms when:
- You're following a pattern from a UK-based designer or publisher - You bought a vintage pattern book (pre-1990 British patterns almost always use UK terms) - You're reading an Australian, New Zealand, or South African pattern (they follow UK conventions) - An online pattern doesn't specify which system it uses - You're translating a pattern for a friend who uses the other system
The UK to US Converter handles the conversion instantly, but knowing the full chart by heart will save you time every time you pick up a new pattern.
Complete UK to US Crochet Stitch Conversion Table
This is the definitive conversion chart. Every stitch shifts up by one position when converting from UK to US:
Chain (ch) = Chain (ch) — same in both systems Slip stitch (ss) = Slip stitch (sl st) — 0 yarn overs Double crochet (dc) = Single crochet (sc) — 0 yarn overs Half treble (htr) = Half double crochet (hdc) — 1 yarn over Treble (tr) = Double crochet (dc) — 1 yarn over Double treble (dtr) = Treble crochet (tr) — 2 yarn overs Triple treble (ttr) = Double treble crochet (dtr) — 3 yarn overs Quadruple treble (qtr) = Triple treble crochet (ttr) — 4 yarn overs
Notice the pattern: chain and slip stitch are the same in both systems. After that, every UK term maps to the US term one step shorter in name. The "yarn overs before inserting the hook" column stays constant — it's only the names that shift.
Additional Stitch Terms That Differ:
Beyond the basic stitches, some pattern instructions also use different vocabulary:
Tension = Gauge Tension square = Gauge swatch Miss (a stitch) = Skip (a stitch) Yarn round hook (yrh) = Yarn over (yo) Raise / relief = Front post / back post Work straight = Work even Cast off = Bind off / fasten off Colour = Color
These non-stitch terms trip people up just as often as the stitch names. A pattern that says "miss 2 stitches" means skip 2 stitches, not that you made an error.
How to Identify Which System a Pattern Uses
Before you start crocheting, figure out which terminology the pattern uses. Here are the reliable tells:
It's a UK pattern if: - It uses the word "tension" instead of "gauge" - It includes "dc" but the gauge seems too short for double crochet (it's actually single crochet) - It references "treble" as the standard medium-height stitch - The designer is based in the UK, Australia, New Zealand, or South Africa - It uses "miss" instead of "skip" - It uses "yrh" (yarn round hook) instead of "yo" (yarn over) - Measurements are given in centimetres first
It's a US pattern if: - It says "gauge" instead of "tension" - It uses "sc" (single crochet) — this stitch doesn't exist in UK terminology - It references "skip" instead of "miss" - The designer is US or Canadian based - It uses "yo" for yarn over
The one foolproof shortcut: If a pattern mentions "single crochet" or uses the abbreviation "sc," it's definitely US terminology. The UK system has no stitch called single crochet — that's the clearest giveaway.
How the UK to US Converter Works
The UK to US Converter translates stitch abbreviations and full terms in both directions. Type in a UK pattern instruction, and it'll output the US equivalent (or vice versa).
It handles: - Individual stitch abbreviations (dc to sc, tr to dc) - Full pattern rows ("3dc, 2ch, miss 1, 3tr" to "3sc, 2ch, skip 1, 3dc") - Vocabulary terms (tension to gauge, yrh to yo)
This is especially useful for long patterns where manually converting every abbreviation is tedious and error-prone.
Vintage Pattern Considerations
Patterns from before the 1980s present extra challenges beyond the UK/US split:
Pre-1960s British patterns often use older terminology that doesn't map cleanly to modern terms. "Afghan stitch" might mean Tunisian simple stitch. "Solomon's knot" appears under several different names.
Hook sizes changed. Old UK patterns use a numbered steel hook system (UK 14 = modern 2mm, UK 8 = modern 4mm) that runs backward from the modern metric system. Old US patterns used letter sizing (H = 5mm, J = 6mm) that's still partially in use.
Stitch heights were sometimes inconsistent. Some mid-century patterns used "double crochet" to mean what we'd now call a half double crochet (hdc). If the gauge doesn't match and you've already confirmed the terminology system, the pattern might be using a non-standard stitch definition.
Thread crochet adds another layer of confusion. Steel hook numbers, thread sizes (10, 20, 30), and vintage lace terminology all use conventions that differ from yarn crochet.
When in doubt with a vintage pattern, crochet a gauge swatch using the stitch the pattern seems to indicate. If the dimensions don't match the stated gauge, try the next stitch up or down in height.
Common Mistakes When Converting Terms
Mistake 1: Converting only some stitches. If a UK pattern uses both "dc" and "tr," you need to convert both — dc becomes sc and tr becomes dc. Converting just one creates an impossible pattern.
Mistake 2: Converting a US pattern to US. Before converting, confirm the pattern actually needs conversion. If you see "sc" anywhere, the pattern is already in US terms. Running it through a converter again would shift everything wrong.
Mistake 3: Forgetting turning chains change. In UK terminology, a turning chain for double crochet (dc) is 1 chain. That same stitch in US terms (sc) also uses 1 chain. But a UK treble (tr) uses 3 turning chains, and its US equivalent (dc) also uses 3 turning chains. The turning chain count follows the stitch, not the name — so it converts correctly as long as you convert the stitch name.
Mistake 4: Assuming Canadian patterns are US. Most Canadian crochet publications use US terminology, but patterns from Quebec or bilingual Canadian publishers sometimes follow UK conventions. Check for the "sc" test before assuming.
Mistake 5: Mixing up increases. "2dc in next st" in UK means "2sc in next st" in US. The increase method is the same, but misreading the stitch type doubles the wrong stitch height.
Real Project Examples
Example 1: Converting a UK Granny Square Pattern
UK pattern reads: Ch 4, join. Rnd 1: Ch 3 (counts as first tr), 2tr in ring, ch 2, *3tr in ring, ch 2* three times, join.
US conversion: Ch 4, join. Rnd 1: Ch 3 (counts as first dc), 2dc in ring, ch 2, *3dc in ring, ch 2* three times, join.
The UK "tr" becomes US "dc." The chains stay the same. The structure is identical — only the stitch names change.
Example 2: Converting a UK Amigurumi Pattern
UK pattern reads: Rnd 1: 6dc in magic ring. Rnd 2: 2dc in each st around (12). Rnd 3: *1dc, 2dc in next st* around (18).
US conversion: Rnd 1: 6sc in magic ring. Rnd 2: 2sc in each st around (12). Rnd 3: *1sc, 2sc in next st* around (18).
Amigurumi patterns use tight single crochet (US) / double crochet (UK) almost exclusively. If you see a pattern that uses "dc" throughout for a stuffed toy and it's from a UK designer, it's definitely single crochet.
Example 3: Identifying a Mystery Vintage Pattern
You find a 1970s pattern card that reads: "Using a no. 9 hook, make 24 ch. Row 1: 1 dc into 2nd ch from hook, 1 dc into each ch, turn. 23 dc."
The "no. 9 hook" is UK sizing (3.5mm), and "dc" with a 1-chain turning chain is UK double crochet = US single crochet. In modern US terms: Using a 3.5mm (US E/4) hook, chain 24. Row 1: Sc in 2nd ch from hook, sc in each ch across, turn. 23 sc.
Frequently Asked Questions
Why doesn't the UK have a single crochet stitch?
The UK system starts its named stitches at "double crochet" (dc), which is the shortest standard working stitch — equivalent to US single crochet. The UK considers the slip stitch as the simplest stitch and begins naming working stitches at "double." The US system added "single crochet" for that shortest stitch, pushing all other names up by one.
Do Australian crochet patterns use UK or US terms?
Australia, New Zealand, and South Africa all follow UK crochet terminology. If you're working from a pattern by an Australian designer, convert it the same way you'd convert a British pattern. Look for "tension" instead of "gauge" and "dc" meaning single crochet as confirmation before you start.
Can I use the conversion chart for Tunisian crochet too?
Basic Tunisian stitches (Tunisian simple stitch, Tunisian knit stitch, Tunisian purl stitch) use the same names in both UK and US systems. The terminology confusion mainly applies to standard crochet stitches. However, some older UK patterns call Tunisian crochet "Afghan crochet" or "tricot crochet," which are worth knowing if you're working from vintage sources.
What happens if I accidentally use the wrong terminology system?
Your fabric height will be wrong. If you read UK "dc" as US "dc" (double crochet), you'll use a stitch that's roughly twice as tall as intended. Your project will be too tall, use more yarn than expected, and have a looser, more open texture than the designer intended. Always verify the terminology system before starting row 1.
Never Mix Up UK and US Terms Again
Bookmark the conversion chart above or, better yet, run your pattern through the UK to US Converter before you pick up your hook. Five seconds of checking saves hours of frogging.