How much yarn for a crochet blanket border?

The quick answer, by blanket size

Find your blanket size and the number of border rounds you plan. As a rule of thumb, use the low end for short stitches such as double crochet (US single crochet) and the high end for trebles (US double crochet), shells or bobbles; our eight patterns are too few to pin that down, so it’s a general guide. If your pattern states its own border yarn, use that instead.

The figures are metres of yarn and balls of a 295m, 100g DK such as Stylecraft Special DK. Most of the borders we measured were aran or worsted, so the rate is not DK-specific; the cross-check below suggests it holds for DK too. If you work in aran, a 100g ball of Stylecraft Special Aran holds 196m, so divide by 196 instead. Round each border colour up to whole balls on its own.

The perimeter formula

Start with the edge of the blanket. Perimeter = 2 × (width + length). A 120 × 175cm blanket has 2 × (1.2 + 1.75) = 5.9 metres of edge.

Each round sits outside the last one, so it is longer. If a round adds about 1cm to each side, the next round is about 8cm longer: 1cm more on each end of all four sides. Add that up and the total length of all your rounds is roughly rounds × perimeter + 4 × round width × rounds².

For a 5-round border on that blanket, with rounds about 1cm wide: 5 × 5.9 = 29.5 metres, plus 4 × 0.01 × 25 = 1 metre, so 30.5 metres of rounds. At 16 to 24 metres of yarn per metre of round, that’s 488 to 732 metres, or 1.7 to 2.5 balls of 295m. The 1cm round width is a middle value, not a measurement of your border: Becky Skuse’s four-round DK border takes her baby blanket from 90 to 100cm, about 1.25cm a round, while Jera’s Jamboree says the four rounds on her Mindful Hands DK blanket add just over an inch to each side, nearer 0.7cm a round.

As a cross-check, a 1cm strip of DK fabric at the 1,780 to 2,530 metres per square metre our blanket guide found works out at about 18 to 25 metres per metre of edge, close to the 16 to 24 from the borders. For the whole 5cm-wide border on a single-bed blanket, about 0.3 square metres, that gives 540 to 770 metres, a little above the formula but in the same area.

What eight published borders use

We looked for patterns that give the border yarn as a separate figure, either as its own line in the materials list or as an extra ball in a border colour. For each one we divided the border yarn by the blanket’s perimeter, and by the number of rounds where the pattern states them. Only five patterns state the rounds, so the per-round rate rests on those five.

Easy Moss Stitch, whose border-colour rounds are double crochet (US single crochet), and Twilight Haven came out lowest, at about 16 to 17 metres per metre of edge per round, even though Twilight Haven’s last two rounds are treble groups. Banana Moon Studio’s sawtooth edging and the border-colour rounds on Cherry Heart’s Florentines, which finish with a pom-pom edging, came out at about 21 to 22. Relaxing Waves gives a single figure, 300 to 450 yards, for all four sizes from throw to king; the pattern doesn’t say which goes with which, so pairing the low figure with the throw and the high one with the king is our own reading, which gives 19 to 24. We set the table at 16 to 24 so the top end leaves room for bulky rounds.

Some of these figures are amounts to buy, not amounts used: a whole ball or two skeins the designer tells you to get. The real use is lower, so those rates are upper limits. The table marks which is which.

Why corners and taller stitches add yarn

Most borders work extra stitches into each corner, often a group such as 2 trebles, 2 chains and 2 trebles. That keeps the corner flat, and it is why every round is longer than the one before. On a small blanket the effect is bigger: 8 rounds on a 76 × 76cm pram blanket add about 2.6 metres of round length to the 24 metres you’d expect from the plain perimeter, roughly 10% more yarn.

Stitch height matters too. A round of trebles is taller than a round of double crochet and uses more yarn per stitch, and bobbles, puffs and shells use more again, though a taller round also covers more width, so fewer rounds may be needed. Jera’s Jamboree’s six-round border on her Blossom Cottage blanket, with one round of bobbles, adds 5 inches to a 42-inch square. If your border has a textured round, budget it at the top of the range.

How big a share of the blanket is the border

Where the pattern also gives the total yarn, the border was between about 5% and 15% of it, and half of them sat between 6% and 8%. Narrow borders on big blankets sit at the bottom: Cherry Heart’s Battenberg blanket used 2 of its 26 balls of the main colour for the border, about 5% of the yarn by weight. Wider or decorative borders sit higher: the three border-colour rounds on Florentines take 140g of a 960g blanket.

Pattern totals already include the designer’s border, and so do the ball counts in our blanket guide, which come from those totals. You only need to add a border on top if your own estimate covers the body alone, say from a weighed swatch; then 7 to 10% of the body yarn is a fair figure for a few rounds. That is the border’s own yarn, not a spare-yarn margin. Put the border colour on its own line when you plan, because one shade carries all of it.

Measure your own rate with one round

Weigh your border ball before and after the first full round. Divide the grams used by your blanket’s perimeter in metres to get grams per metre of edge per round. Multiply by the perimeter and the number of rounds, then add a little for the corners.

Say the first round on a 5.4-metre edge uses 30g. That’s about 5.6g per metre of edge. Five rounds would take about 150g, plus a little for the growing corners, so buy 2 balls of 100g. Weigh a taller round separately if your border mixes stitches.

Buying the border yarn

Border yarn is the last thing you crochet, so it is easy to run short when a shop no longer has the same dye lot. Buy the border colour with the rest of the yarn and keep the ball band.

Add the border metres as their own row in the yarn budget calculator, then check the spare-yarn guide for how much over to buy. If the border uses the same shade as the body, add the two quantities together before rounding up to whole balls.

Common questions

Sources and scope

• www.jerasjamboree.co.uk/free-crochet-lap-blanket-pattern-twilight-haven/
• catherinecrochets.com/easy-moss-stitch-crochet-blanket-a-relaxing-crochet-project-to-snuggle-up-with/
• sunflowercottagecrochet.com/relaxing-waves-blanket-easy-and-free-crochet-blanket-pattern/
• bananamoonstudio.com/sawtooth-crochet-edging-tutorial/
• bananamoonstudio.com/fall-crochet-along-blanket-pattern/
• www.cherryheart.co.uk/2016/03/spice-of-life-crochet-along-blanket.html
• www.cherryheart.co.uk/2016/03/giant-granny-square.html
• www.cherryheart.co.uk/2025/08/florentines-blanket.html
• www.cherryheart.co.uk/2018/12/battenberg-blanket.html
• simply-yarn.com/crochet-patterns/easy-free-granny-square-baby-blanket-crochet-pattern
• www.jerasjamboree.co.uk/mindful-hands-mosaic-blanket-free-crochet-lap-pattern/
• www.jerasjamboree.co.uk/granny-square-blanket-blanket-blossom-cottage/
• www.stylecraft-yarns.co.uk/yarns/special-dk
• www.stylecraft-yarns.co.uk/yarns/special-aran

Sources checked 2 October 2026. Label facts come from the linked references; worked purchase examples and arithmetic are our own illustrations.