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. Type a value and get the right number right away, with the math handled for you.
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, but 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, where typing in either box updates the other 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.
More tools from Skein.
A free toolkit for everything you measure, swatch, or substitute. No sign-up required.
Open tool →Yarn Calculator
Your pattern gives you a yarn name. Not a skein count. Enter your yardage and weight, Yarnzy returns the exact number of skeins. Not a guess. The real number.
Open tool →Stitch Calculator
Know your gauge. Know your width. Yarnzy does the one calculation every knitter skips and every frogged project proves they shouldn't have.
Open tool →Yarn Substitution
Your pattern's yarn is discontinued. Enter your yardage and weight, get the exact skein count for whatever yarn you're swapping in. Before you buy anything.
Open tool →Increase & Decrease Calculator
Even shaping doesn't happen by feel. Enter your stitch count and rows, Yarnzy spaces every increase and decrease so your finished piece shows it.
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