Knitting & Crochet calculator
Knitting Calculator: Gauge, Cast On and Increase Evenly
Stitches and rows from your gauge, how many stitches to cast on for a hat, pattern gauge conversion, and how to increase or decrease evenly.
Your knitting
Stitches for your widthExample gauge
90 stitches
and 60 rows for 20 in × 10 in
- Your gauge
- 18 sts and 24 rows per 4 in
- Per inch
- 4.5 sts, 6 rows
- Actual size
- 20 in × 10 in
- Typical yarn weight
- #4 Medium
Stitch counts are rounded to the nearest whole stitch. Measure your swatch after washing and blocking it like the finished piece.
90 stitches · 60 rowsYour knitting notes
- Cast on: 90 stitches
- Work: 60 rows
- Gauge: 18 sts and 24 rows per 4 in
- Finished size: 20 in × 10 in
How many stitches to cast on for a hat
Stitches to cast on in the round for 2x2 rib (a multiple of 4) with 2 in of negative ease, from the same math as the calculator. Gauge in stockinette stitches per 4 in.
| Size | 16 sts | 18 sts | 20 sts | 22 sts | 24 sts |
|---|---|---|---|---|---|
| Preemie, 1–2 lb9 in head22.9 cm head | 28 | 32 | 36 | 40 | 44 |
| Preemie, 3–4 lb11 in head27.9 cm head | 36 | 40 | 44 | 48 | 56 |
| Preemie, 4–5 lb12 in head30.5 cm head | 40 | 44 | 52 | 56 | 60 |
| Preemie, 5.5–6 lb13 in head33 cm head | 44 | 48 | 56 | 60 | 68 |
| Newborn14 in head35.6 cm head | 48 | 56 | 60 | 68 | 72 |
| Baby, 3–6 months17 in head43.2 cm head | 60 | 68 | 76 | 84 | 92 |
| Baby, 6–12 months18 in head45.7 cm head | 64 | 72 | 80 | 88 | 96 |
| Toddler, 1–3 years19 in head48.3 cm head | 68 | 76 | 84 | 92 | 104 |
| Child, 3–10 years20 in head50.8 cm head | 72 | 80 | 92 | 100 | 108 |
| Preteen and teen21 in head53.3 cm head | 76 | 84 | 96 | 104 | 116 |
| Adult woman22.5 in head57.2 cm head | 84 | 92 | 104 | 112 | 124 |
| Adult man24 in head61 cm head | 88 | 100 | 112 | 120 | 132 |
Head sizes: Knit Picks hat size chart. Your gauge in the rib may differ: swatch it.
Decrease evenly chart
Common evenly spaced decreases with k2tog, from the same math as the calculator.
| Stitches | Worked flat | In the round |
|---|---|---|
| 64 − 8 = 56 | [K6, k2tog] 3 times, [K5, k2tog] 5 times, K5. | [K6, k2tog] 8 times. |
| 72 − 6 = 66 | [K9, k2tog] 4 times, [K8, k2tog] 2 times, K8. | [K10, k2tog] 6 times. |
| 80 − 8 = 72 | K8, k2tog, [K7, k2tog] 7 times, K7. | [K8, k2tog] 8 times. |
| 88 − 8 = 80 | [K8, k2tog] 8 times, K8. | [K9, k2tog] 8 times. |
| 96 − 12 = 84 | [K6, k2tog] 7 times, [K5, k2tog] 5 times, K5. | [K6, k2tog] 12 times. |
| 100 − 8 = 92 | [K10, k2tog] 3 times, [K9, k2tog] 5 times, K9. | [K11, k2tog] 4 times, [K10, k2tog] 4 times. |
| 120 − 8 = 112 | [K12, k2tog] 5 times, [K11, k2tog] 3 times, K11. | [K13, k2tog] 8 times. |
| 144 − 12 = 132 | [K10, k2tog] 3 times, [K9, k2tog] 9 times, K9. | [K10, k2tog] 12 times. |
Every row matches the decrease chart published by Yardage Lab.
Abbreviations in the instructions
| Abbreviation | Meaning |
|---|---|
| K | Knit |
| M1 | Make one: a new stitch between two stitches, uses none |
| kfb | Knit into the front and back of one stitch: 1 becomes 2 |
| k2tog | Knit 2 stitches together: 2 become 1 |
| M1P, pfb, p2tog | The same three, worked purlwise on a wrong-side row |
| [ ] … times | Work what is in brackets the number of times given |
| * … rep from * | Repeat from the star; “in all” counts the first time too |
US terms, following the Craft Yarn Council's knitting abbreviations.
https://homedosh.com/knitting-calculator/
Knitting gauge calculator: stitches and rows for any size
Stitches per inch = stitches in your swatch ÷ its width; rows the same with its height. Stitches = width × stitches per inch, rounded to the nearest whole stitch (halfway rounds up). We show the size you actually get with that count and the Craft Yarn Council yarn weight your gauge is typical for. Measure over at least 4 in after washing and blocking the swatch: Interweave shows how half a stitch per inch turns a 40 in sweater into 35½ in.
Pattern gauge to your gauge
Stitches at your gauge = pattern stitches × your gauge ÷ pattern gauge, and rows the same with the row gauges. Within a quarter stitch per 4 in we call it on gauge; that tolerance is our assumption, about half the precision of counting a swatch. More than 2 stitches or 10% apart gets a warning, the same rule as our Yarn Calculator. As Interweave explains, more stitches per inch than the pattern means a larger needle, fewer means a smaller one. A new stitch count changes the pattern's repeats and shaping, so check them.
Cast on calculator: hats, scarves and rib repeats
Measurement minus negative ease, times stitches per inch, gives the exact count. We round it to the nearest count that fits the pattern repeat and show the counts on either side with their sizes. A tie rounds up, because ribbing pulls in. 2x2 rib needs a multiple of 4 in the round and 4 plus 2 on a flat piece, so both edges match; 1x1 rib and seed stitch a multiple of 2, plus 1 flat. Edge stitches for seaming go on top and are not part of the width. For hats, Knit Picks says 2 in (5 cm) of negative ease is most common; use 0 for a scarf or blanket.
Increase evenly calculator: M1 or kfb across a row or round
M1 makes a new stitch between two stitches and uses none; kfb knits into the front and back of one stitch, so it uses one. The remaining plain stitches are shared out between the increases: one more gap than increases on a flat piece, so the row starts and ends with plain stitches, and as many gaps as increases in the round. Gaps differ by at most one stitch. The easy version works the longer gaps first so it reads as two repeats; the most even version spreads them out. Lion Brand's guide walks through the same method by hand.
Decrease evenly with k2tog
Each k2tog uses two stitches and leaves one, so plain stitches = stitches now − 2 × decreases, shared out the same way. In one row you can decrease at most half your stitches, and with M1 increase at most one fewer than your stitches on a flat piece; past that, the calculator tells you to spread the rest over the next row or round. Every instruction is checked: plain stitches plus the stitches used add up to the count you started with.
Our assumptions
- Stitch counts round to the nearest whole stitch, halfway up. Cast on counts round to the nearest pattern repeat, halfway up.
- “On gauge” means within 0.25 stitch per 4 in. That tolerance is ours, not a standard.
- The hat table uses 2x2 rib, 2 in of negative ease and your stockinette gauge. Ribbing is stretchier than stockinette, so swatch in the stitch you will use.
- On a wrong-side row, purl the plain stitches and use M1P, pfb or p2tog. The spacing stays the same.
- Lengths convert at exactly 2.54 cm per inch. A gauge over 10 cm is treated as over 4 in when you switch units, as yarn labels do.
Questions people ask
How many stitches do I cast on for a hat?
Head size minus negative ease, times your stitches per inch, rounded to your rib repeat. For an adult woman (22.5 in head) with 2 in of negative ease at 18 stitches per 4 in, that is 20.5 × 4.5 = 92.25, so cast on 92 for 2x2 rib in the round. The table above lists every size.
How do I calculate stitches from my gauge?
Divide the stitches in your swatch by its width to get stitches per inch, then multiply by the width you want. 18 stitches over 4 in is 4.5 per inch, so a 20 in wide piece needs 90 stitches. Rows work the same way with your row gauge and the length.
What if my gauge doesn't match the pattern?
More stitches per 4 in than the pattern means your stitches are smaller: try a larger needle. Fewer means try a smaller needle. Or recalculate the stitch count: a pattern written for 180 stitches at 20 per 4 in needs 216 stitches at 24 per 4 in for the same width. That changes the pattern's repeats, so check them.
How do I increase evenly across a row?
Share the stitches out into equal gaps and work an increase in each gap. On a flat piece there is one more gap than increases, so the row starts and ends with plain stitches. To increase 12 stitches across 96: [K8, M1] 5 times, [K7, M1] 7 times, K7. That gives 108 stitches.
How do I decrease evenly in the round?
Take two stitches off the count for each k2tog, then share the rest out equally: in the round there is one gap per decrease. With 80 stitches and 10 decreases, 60 plain stitches make gaps of 6, so work [K6, k2tog] 10 times. That leaves 70 stitches. The decrease chart above lists more common counts.
Should I use M1 or kfb?
Both add one stitch. M1 makes a new stitch between two stitches and uses none; kfb knits into the front and back of one stitch, so each one uses a stitch. With kfb there are fewer plain stitches between the increases, which the calculator takes into account.
Why are flat and in-the-round instructions different?
In a row the increases or decreases sit between the two edges, so there is one more gap than changes. In the round the last gap meets the first, so gaps and changes are equal and no stitches are left over at the end.
How much negative ease does a hat need?
Knit Picks' hat size chart says that for a snug beanie 2 in (5 cm) of negative ease is most common, so the hat is a little smaller than the head and stays on. Less ease gives a slouchier fit. Size presets in the Cast on mode use 2 in; change it under More options.
Is gauge per 4 inches the same as per 10 cm?
Nearly. 10 cm is 3.94 in, so a count over 10 cm is about 1.6% lower than over 4 in. Yarn labels print the two as the same gauge. The calculator uses exactly the width you enter, and switching units turns 4 in into 10 cm and back.