Download the AppUnit Conversion Calculator for Yarn, Knitting & Crochet
Convert yarn measurements instantly: meters to yards, grams to ounces, and millimeters to inches. Yarnzy's unit conversion tool was built by crafters, for crafters, so every number makes sense.
Download Yarnzy on iOS & AndroidLive Unit Conversion Tool
Fast, accurate conversions for crochet, knitting, weaving, and all your yarn projects. No math, no mistakes, no stress — just the right number, right away.
Type fractions like "3 1/2" or "1/4" directly — both work.
The gauge conversion that trips everyone up.
18 sts per 4 inches and 18 sts per 10 cm sound the same — they aren't. 4 inches is 10.16 cm, not 10. Here's exactly how the math works so you can convert any pattern's gauge cleanly.
4 in = 10.16 cm
18 sts / 4 in ≠ 18 sts / 10 cm
4 inches is 10.16 cm, not 10 cm flat.
Step 01 · The trap
4 inches is not 10 cm.
Most people round 4 in to 10 cm — but that 0.16 cm matters. A pattern says "18 sts / 10 cm" expects fewer stitches per 4 inches than a pattern that says "18 sts / 4 inches."
Step 02 · Sts per cm
Divide stitches by actual length.
Get density per cm by dividing. This is the precise per-cm value — the bridge to any other measurement unit.
Step 03 · Sts per 10 cm
Multiply by 10.
The shortcut: multiply 4-in count by 0.9843 to get sts / 10 cm. Or use the gauge tab above — type in either box and the other updates instantly.
How to Use the Unit Converter
Three simple steps — no account, no setup. Open the converter, pick your measurement type, and read the result instantly as you type.
01
Open the Converter
Tap the Unit Conversion tool inside Yarnzy or scroll up on this page. No account, no registration, no setup needed — it opens instantly and you're ready to convert right away.
02
Choose Your Conversion Type
Select the type of measurement your pattern needs — length, weight, or hook and needle sizing. Everything is clearly labeled so you find the right option in just a few seconds.
03
Enter Your Value and Get Results
Type the number from your pattern, yarn label, or gauge swatch — whole or decimal, any value works. Your result appears automatically as you type so you can get back to crafting.
Frequently Asked Questions
Exact numbers for the conversions makers reach for most — millimeters, inches, grams, ounces, yards, and meters.
There are exactly 25.4 millimeters in one inch — this is a fixed, internationally standardized conversion. A 5mm crochet hook equals about 0.197 inches, and Yarnzy converts any millimeter value to inches instantly.
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Convert Yarn Measurements Instantly with Yarnzy
Save time, avoid costly mistakes, and convert yarn units accurately for every single project. From your very first stitch to your last row, Yarnzy is the one tool always worth having open.
Built for crocheters & knitters · Accurate yarn conversion · Beginner friendly
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