Free Online Calculators for Knitters and Crocheters

Free online calculators for knit and crochet

I’m a math nerd and a knit nerd and a crochet nerd and I’m happy to proclaim that to the world. I like the calculations that crop up on knit and crochet projects. I like to work them by hand or in a spreadsheet. Sometimes I make a little graph too, not because I need one but because I really like graphs and I think there should be more of them in the world.

But the truth is there are bigger nerds out there than me. There are nerds who have risen high into the stratosphere of nerddom and they leave me completely in the dust. I’m talking about those yarn-loving nerds that write computer programs for solving their yarn math. Then they turn those programs into human-friendly web pages. Then they post them on the internet so they can be enjoyed by people who perhaps do not think there should be more graphs in the world everyone.

These are pretty talented yarn nerds. Aren’t we lucky to have them?

I’ve put together a round-up of my favorite free online calculators for knitters and crocheters. I use them. I like to check my work. So give them a try and if you like them too, maybe send a short thank-you to the developer. After all, the whole crafting world benefits when an uber yarn nerd writes a computer program that does all your maths for you. We need to encourage these special people. Maybe they will write more…

Free Online Calculators for Knitters and Crocheters


Biscuits and Jam’s Random Stripe Generator

from Bicuits and Jam's random Stripe Generator

Good for: knitting & crochet

What it does: This widget allows you to select almost any number of colors (from 2 to 77), set the width(s) of the stripes you want to have, and toss in the total number of rows to work with. Then it generates a random stripe pattern in graphical and text form. Don’t like they way that turn out? Hit refresh and you’ll get another pattern.

Bonus: If you have less of one color than another, try the weighted random stripe generator.

Eskimimi’s Knitulator

Good for: knitting & crochet

What it does: This widget will help you spread out your increases or decreases evenly. If you’re decreasing for an arm cuff or increasing for a slouchy hat, your work will work best if you get those spaced out evenly. It works even if the number you have aren’t “perfect” (like you have 50 stitches and need to decrease by 8). Just plug in your numbers and you’ll get a line of instructions with two options for increase stitches. I’m saying this works for crocheters too. Just replace that “kfb” with “work two sc/dc in same stitch” .  

I Aten’t Dead’s Knitting Pattern Convertor

Good for: knitting & crochet

What it does: Its a converter for when you want to work a pattern in a different size yarn/needle/gauge, for when you can’t or just don’t want to get the gauge called for in a pattern. Its ultra-stripped down (no graphics). You’ll need the gauge info from the pattern (stitches per inch & rows per inch) and your gauge. Then enter in how many stitches the pattern says to cast on or bind off or how wide you want your piece to be or any of the other factors. This widget gives you some choices. Then click calculate for your customized instructions.

Jimmy Beans’s Wool’s Yarn Estimator


from Jimmy Bean's Wool Knitting EstimatorGood for: knitting

What it does: It estimates how much yarn you’ll need for a project, almost any project. Set it to imperial or metric, tell it what you want to make, and what size you want to make it in. Then give it a gauge, a stitches/inch. Pulling that from a pattern or from the ballband should work just fine. Then calculate. Then add on 10% before you start just to be sure! 

The Crochet Crowd’s Afghan Calculator

Afghan Size CalculatorGood for: crochet

What it does: So you’ve found a crochet stitch you like and you think it will make a nice blanket. How many stitches do you chain? Ah ha! That’s what this calculator is good for. You’ll need to chain for about 6 inches and then count. Then head over to the calculator. Plug in how many chains it takes for you to make 4 inches. Then get your stitch pattern. Tell the calculator how many stitches are in each repeat (of say your ripple) and then tell it how many are for the edges. Then you need to tell it how big your blanket should be. That’s enough to get your starting base chain. If you want to figure out how many rows you need, keep going down the page.

The Knitting Fiend’s Sock-u-lator

The sock-u-latorGood for: knitting

What it does: The sock-u-lator will generate a basic cuff-down pattern for a sock of any size with and yarn. You’ll need to know your gauge and this is pretty important. The fit of any sock is all about the gauge. Then tell the calculator what size shoe your future-sock owner has. You can play around with the ribbing length or length of the leg. And ta-da! You have a sock pattern complete with clickable tutorials for each section.

Bonus: The Knitting Fiend also has a sweater calculator. Its… involved. You’ll have to read all the instructions to make it work correctly. But it can give you a sweater pattern for any shape and any yarn. Its takes some playing around to get the hang of it but that’s because its a very powerful widget.


Knit and crochet math made easy… because you didn’t have to do to any of it! Take my advice and bookmark all of these free online calculators for knitters and crocheters. You’ll need them, its only a matter of time. I certainly have. They are on this list of Stuff Jenn Likes

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17 Comments on "Free Online Calculators for Knitters and Crocheters"

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More crafting bookmarks for me yay! Adding to the stuff Jen doesn’t like (probably): No baby yet. We definitely dropped down further though since I can once again breathe, but Sprout is still all warm, snug, and growing those ever important lungs 🙂


Rae, my daughter and my niece both swear by a tradition in our family: meatloaf and green beans. So far, five babies, and when either of them was overdue by a day, we made meatloaf and green beans. Magically, labor and delivery soon followed! Best of luck!

Thank you Jenn for this info. I’m sure it will be helpful in time when I’m more confident about my knitting. How you come up with all this info is just amazing to me. I am technically challenged when it comes to the Internet. Guess it has something to do with my age. My 8 and 9 year old grand children run circles around me on the Internet. They show me how to perform certain tasks on the computer every time they come to visit. They even surprise my daughter with their knowledge when I ask her if she was… Read more »

You are the best! These are wonderful tools to have. Even as long as I have been crocheting I will still have the ooccasional problem when I start tinking around with a pattern. My knitting is still in the learning stage (and may be there a while). These are going to be sooo helpful. Thank you for sharing. I would have never found these on my own.


Jenn, do you ever sleep, or just thrive on coffee and finding awesome yarn-y good stuff for all of us? The increase/decrease calculator is a huge time saver!

A shout out to mommy-to-be Rae: My daughter was two weeks overdue. Tell the kiddo it has to stay in there. They never listen 🙂


Excellent roundup – thanks, Jenn!