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Convert leather thickness between ounces, millimeters, and irons. Standardize leather weight specs for tooling, stitching, and pattern layout projects.
Calculate leather square footage from pattern pieces and hide dimensions. Free leather area calculator for wallets, bags, belts.
Estimate leather stretch percentage over time for straps, belts, and bags. Free leather stretch calculator for sizing belts, watch bands.
Sum the area of all leather pieces including edges to be finished. For belts and straps, both faces plus edge perimeter × thickness contribute to coverage.
Area (cm²) = Σ (length × width) for each pieceAlcohol dyes cover roughly 1–2 m² per 118 ml (4 oz) on veg-tan. Oil dyes and finishes vary — use manufacturer specs when available.
Dye needed (ml) = (area m² / coverage m² per ml) × coatsVeg-tan absorbs more dye than finished chrome-tan. First coat on dry veg-tan may use 1.5× the finish amount of subsequent coats.
First coat multiplier ≈ 1.3–1.5× for untreated veg-tanUpdated: July 2026
Two coats Fiebing's Pro Dye at 1.5 m²/118 ml: (0.3/1.5) × 118 × 2 ≈ 47 ml. Buy a 118 ml bottle with margin for edge touch-up.
Each belt 100 cm × 3.8 cm edge perimeter ≈ 380 cm² edge surface. Ten belts = 3800 cm². Edge coat at 3 m²/L needs ~13 ml total across three coats.
Bag exterior 0.45 m² plus straps. Two thin Resolene coats at 2 m²/118 ml: (0.55/2) × 118 × 2 ≈ 65 ml — one 4 oz bottle suffices.
Thick coats dry unevenly, rub off, and waste product. Multiple thin coats with drying between give better color and actually use less total material.
Add 15–20% extra for test pieces, brush absorption, and container residue. Custom-mixed colors cannot be easily matched if you run short.
Running out of dye mid-project causes color-matching headaches. This calculator estimates dye, finish, and edge coat quantities from total leather surface area, number of coats, and product-specific coverage rates.