How Skein Tally works
Skein estimate (per pattern colour)
stitch-equivalents = full + 0.5 × half + 0.25 × quarter + 0.75 × three-quarter
single-strand metres = stitch-equivalents × cross strands × L + backstitch × 0.62 × backstitch strands × L + extra metres × cross strands, where L = (8 m × 6) ÷ (base × 2) × 14 ÷ effective count.
skeins = metres ÷ (skein length × strands per skein) × (1 + allowance), rounded up for display. If the pattern lists skeins, that number is used instead.
Defaults (all assumptions, all editable)
- Base: 1,500 full crosses per skein on 14-count with 2 strands. Published figures range from about 960 to 1,900 (sources).
- Allowance: 10 %.
- Skein: 8 m, 6 strands (a common six-strand cotton skein).
- Partial-stitch and backstitch weights: simple geometry, not measured.
- Fabric margin: 3 in (7.6 cm) per side.
Shopping list
For active, included projects, need is summed per brand + number (case and spaces ignored), your stash is subtracted, and the rest is rounded up per colour. Coverage per project allocates stash in project-list order.
Tests
Unit tests check the scaling against hand calculations and a published chart's proportions, rounding, shopping aggregation, stash matching, fabric sizes, file import safety and a large-stash performance case. Browser tests on desktop and mobile check every page and the planner flows. They check exports and that the planner makes no network requests beyond loading the site. PDFs are checked independently with poppler.
These are planning estimates, not guarantees. Your own stitching habits matter more than any formula.