Using a different yarn than the pattern asks for? Enter the pattern yarn's length per skein and number of skeins, then your yarn's label, to see how many skeins to buy. Add grams or weight categories and the calculator checks whether the two yarns are a good match.
Last updated:
Yarn in the pattern
For the size you are making.
g
Your yarn
g
$
%
Covers gauge differences and swatching.
Enter your values to see the result.
Advertisement
Advertisement
How to use the Yarn Substitution Calculator
Enter the pattern yarn: length per skein, skeins for your size, and grams and weight if listed.
Enter your yarn's label: length per skein, grams and weight category.
Set a safety margin: 10% is a good default.
Buy the skeins shown, and check the compatibility verdict before you start.
Yarn substitution formula
Total yardage = pattern yarn length per skein × number of skeins
Skeins of your yarn = ⌈total yardage × (1 + safety margin) ÷ your yarn's length per skein⌉
Thickness (grist) = yards per skein ÷ grams per skein × 100 = yards per 100 g
Example: a pattern needs 5 skeins of 220 yd (1,100 yd). Your yarn has 200 m per skein, which is 218.7 yd. With 10% extra you need 1,210 ÷ 218.7 = 5.53, so buy 6 skeins.
Standard yarn weights at a glance
Category
Common names
Typical yd per 100 g
Knit gauge (sts per 4 in)
0 Lace
Lace, cobweb, light fingering
about 600 or more
33–40
1 Super fine
Fingering, sock, baby
about 350–500
27–32
2 Fine
Sport, baby
about 290–350
23–26
3 Light
DK, light worsted
about 215–290
21–24
4 Medium
Worsted, aran, afghan
about 155–215
16–20
5 Bulky
Chunky, craft, rug
about 95–155
12–15
6 Super bulky
Super chunky, roving
about 40–95
7–11
7 Jumbo
Jumbo, roving
under about 40
6 or fewer
Gauge ranges follow the Craft Yarn Council's Standard Yarn Weight System. Yards per 100 g are typical values and vary with fiber: dense fibers such as cotton have fewer yards per 100 g than wool of the same thickness.
Tips for substituting yarn
Match the fiber behavior as well as the weight: cotton and linen have less stretch than wool, and alpaca drapes and grows more.
Always swatch, wash and dry the swatch before measuring gauge.
Buy all skeins from the same dye lot, and note the lot number in case you need more.
If your yarn is a little thinner, you can sometimes go up a needle size; if it is much thinner, consider holding two strands together and re-checking gauge.
Frequently asked questions
How do I calculate how much substitute yarn I need?
Multiply the length per skein of the pattern's yarn by the number of skeins to get the total yardage, add a safety margin, then divide by the length per skein of your yarn and round up. For example, 5 skeins of 220 yd is 1,100 yd; with 10% extra that is 1,210 yd, which is 6.05, so 7 skeins of a 200 yd yarn.
Why can't I just buy the same number of skeins?
Skeins come in very different lengths. A 100 g skein of worsted might have 180 yd or 220 yd, so buying by skein count can leave you short. Always compare total yards or meters.
How do I know if a yarn is a good substitute?
Look for the same weight category and a similar number of yards per 100 g (within about 10%). Then knit or crochet a gauge swatch with the recommended needle or hook, because fiber, ply and construction also affect gauge and drape.
What are the yarn weight categories?
The standard categories run from 0 to 7: 0 lace, 1 super fine (fingering, sock), 2 fine (sport), 3 light (DK), 4 medium (worsted, aran), 5 bulky (chunky), 6 super bulky and 7 jumbo. They come from the Craft Yarn Council's Standard Yarn Weight System and are printed on many labels.
How do I convert meters to yards for yarn?
Divide meters by 0.9144 to get yards, or multiply yards by 0.9144 to get meters. For example, 200 m is about 219 yd.
Should I buy extra yarn?
Yes. Different yarns rarely give exactly the same gauge, and running out can mean a different dye lot. An extra 10% (or one extra skein) is a common choice, and many shops accept returns of unopened skeins.
Are all the tools on FreeToolCabin tested for quality and accuracy?
Yes! Every tool on our site undergoes automated Q/A testing in real browser environments to ensure high precision, correct output, and zero errors. If you happen to spot a bug or have a suggestion, please contact us at [email protected] and our team will review it right away.