Macramé cord calculator
How long to cut each cord for a wall hanging, plant hanger or bag, and how much cord to buy. The multiples are rules of thumb, so adjust them to your own knotting.
How the estimate works
Knots eat cord. A strand worked in square knots all the way down uses far more than one that hangs straight. The calculator multiplies the finished length by a knotting multiple, adds the fringe, and doubles it when each cord folds in half over the dowel, since one cut cord then gives two strands.
These multiples are rules of thumb, not measurements: about 3× for light, open patterns, 4× for most pieces and 5× for dense knotting. Cord thickness and how tightly you knot change the answer.
Get your own multiple
Knot a 10 cm (4 in) sample of your pattern with a measured strand. Divide the cord it used by the length it made: that is your multiple. Type it into “Each strand is” and keep the spare for mistakes and offcuts.
Questions
Why is the cut length double the strand length?
Because a cord folded in half with a lark's head knot hangs as two strands, and each strand needs the full length.
What if I run short?
Cutting long is safer than joining cord mid-piece. If in doubt, raise the multiple or the spare.
Does the fringe count as finished length?
No. Enter it separately: it is added to each strand once, without the knotting multiple.
Sources
- Knotting multiples: common crafters' rules of thumb with no published standard behind them, which is why they are labelled as such and can be changed.
- National Institute of Standards and Technology, Guide to the SI, Appendix B.9: 1 inch = 2.54 cm, 1 foot = 30.48 cm and 1 yard = 0.9144 m.