Welding Wire Consumption Calculator
Inputs
Fields start empty. The example's 80% efficiency is only an illustration, not a figure for your process.
Get this from the Fillet Weld calculator or your own takeoff.
Share of wire that ends up in the weld. Use your wire manufacturer's data or your own measurements.
Enter deposited weld metal and a deposition efficiency to see results.
Efficiency varies with process, wire type, shielding gas, settings and technique, so this calculator doesn't assume one. Check your wire manufacturer's data sheet, or weigh wire used against weld metal deposited on a test piece.
How it works
Not all wire fed through the gun ends up in the weld. Some is lost to spatter, fumes, cut-off ends and, for flux-cored wire, slag. Deposition efficiency is the share that becomes weld metal.
Wire required = deposited weld metal ÷ (efficiency % ÷ 100) Process loss = wire required − deposited weld metal Spools = wire required ÷ spool size (rounded up to whole spools)
Why there's no default efficiency
Published efficiency figures vary widely by process, wire, gas and settings. Rather than guess, this calculator asks you for the number. Manufacturer data sheets and your own test welds are the best sources.
Worked examples
10 lb deposited, 80% efficiency, 11 lb spools Wire = 10 ÷ 0.80 = 12.5 lb Loss = 2.5 lb Spools = 12.5 ÷ 11 = 1.14 → 2 spools 5 kg deposited, 90% efficiency Wire = 5 ÷ 0.90 = 5.56 kg Loss = 0.556 kg