Welding cost per foot calculator

Filler, gas, power, and labor math for MIG, TIG, and flux-core — with a cost table by material thickness.

The per-foot math

Weld cost per foot = filler + gas + power + labor. Each piece follows from the weld's cross-section and your travel speed:

• Filler: steel weighs 0.283 lb/in³. Fillet weld metal per foot ≈ leg² × 1.7 lb (a 1/4" fillet ≈ 0.11 lb/ft; aluminum at 0.096 lb/in³: leg² × 1.15). At ~95% deposition efficiency for solid wire, divide by 0.95, then multiply by your wire price per pound.
• Gas: flow rate (cfh) × arc time. Arc time per foot = 12 ÷ travel speed (ipm). A 1/4" fillet at 20 ipm needs 0.6 minutes of arc per foot; at 25 cfh of 75/25 that's ~0.25 ft³, so ~$0.06 at $0.25/ft³ bulk mix.
• Power: amps × volts × arc time ÷ 1,000 = kWh. A 130 A × 19 V weld uses ~2.5 kWh per hour of arc — at $0.15/kWh that's under $0.04/arc-hour. Power is almost always negligible.
• Labor: shop rate × arc time ÷ operator factor. Real shops weld maybe 30–50% of the clock (fit-up, tacking, repositioning); multiply arc time by 2–3 for true labor minutes.

Per foot ≈ (wire lb/ft × price) + (cfh × 12/travel-ipm × gas $/ft³) + (A×V×arc-time × $/kWh) + (shop rate × arc-minutes/60 × operator factor)

Cost table — 1/4" steel fillets, $30/hr shop rate, 75/25 gas at $0.25/ft³, $0.15/kWh

Table values assume a 40% operator factor is already baked into labor (arc minutes × ~1.6 for fit-up and positioning) and a 100% duty-cycle machine. TIG costs 2–3× MIG per foot on steel mostly because travel speed is half — the filler itself is cheap.

Why thickness dominates the table

Fillet metal volume scales with leg², so a 1/4" fillet needs 4× the filler of a 1/8" fillet, at roughly half the travel speed — about 8× the arc time per foot. Thicker sections also demand multi-pass work with inter-pass cleaning. That compounding is why the labor column swells faster than the material columns as thickness climbs.

Where the savings actually are

• Travel speed: moving from 10 to 14 ipm on a 1/4" fillet cuts labor ~30%. Bigger wire at higher amps is the lever.
• Wire diameter: 0.045" wire deposits ~50% more metal per amp than 0.035" at the same settings range — fewer passes on 3/16"+ steel.
• Flux-core over gas MIG for thick outdoor work: no gas cost, higher deposition, wind-tolerant.
• Don't overweld: a fillet with legs 1.5× material thickness is nearly always over-designed. Each extra 1/16" of leg adds ~15% to the metal volume.

Dial in your settings first with the thickness calculator, the MIG wire speed chart, and the duty cycle calculator — a machine that trips on thermal overload turns every cost estimate upside down.