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Heddle Calculator

Calculate heddles needed per shaft for loom threading. Plan heddle count from warp ends, shafts, and threading pattern for your loom.

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Inputs that matter
Total Warp Ends, Number of Shafts, Threading
Output to expect
Heddles Per Shaft
  • Check the units and required inputs before comparing results.
  • Keep the assumptions with a copied result so you can reproduce the calculation later.
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Reference & details

How it works

Equal Distribution

For straight threading (1-2-3-4 repeat), ends distribute equally. 400 ends on 4 shafts = 100 heddles per shaft.

Heddles per shaft = Total ends ÷ Number of shafts

Pattern-Weighted Distribution

Complex twills and satin drafts thread unevenly. Read the threading draft to count ends assigned to each shaft individually.

Count ends per shaft from draft

Heddle Capacity Check

Verify each shaft has enough heddles installed. Keep 5–10% spare heddles for pattern changes and repairs.

Available heddles ≥ Required + 10% spare

Updated: July 2026

Example Scenarios

Straight twill threading distributes 90 heddles per shaft. Standard 12-inch shaft with 200 heddles has ample capacity.

Satin draft may put 150 ends on shafts 1 and 5, 75 on others — count from draft, not equal division.

Single rigid heddle with 200 slots/holes handles 200 ends maximum. Double heddle setup for 3-4 shaft patterns requires two heddles.

FAQ

At minimum, one heddle per warp end on each shaft that end uses. For 400 ends on 4-shaft straight draw: 100 heddles per shaft.

Purchase additional heddles matching your loom brand and shaft height (regular vs long). Some weavers tie heddle bundles temporarily for sampling.

Rigid heddles combine heddle and reed function. 'Heddle count' equals slots plus holes (typically equal numbers). One rigid heddle = one shaft equivalent.

Mark each threading column in the draft and tally ends per shaft. Weaving software (Fiberworks, WeaveIt) calculates automatically from entered draft.

Heddles must match shaft height and wire gauge for your loom brand. Universal tie-on heddles exist but check compatibility before purchasing.

About Heddle Calculator

Running short of heddles mid-threading stops your project before weaving begins. Enter total warp ends, number of shafts, and threading pattern to calculate heddles required per shaft and verify your loom capacity.