Welding Heat Input Calculator
kJ/mm from volts, amps and travel speed — with process efficiency.
Heat input drives cooling rate, hardness and distortion. Typical structural windows: 1–2.5 kJ/mm. Quenched-and-tempered steels cap it hard (over-soften); duplex stainless caps both ends.
Formula
Welding Heat Input Calculator is a free heat input welding for welding engineers, fabricators and CWI inspectors — instant, accurate and 100% client-side, with the governing formula and reference shown next to the result so the number can be defended, not just quoted.
About Welding Heat Input Calculator
kJ/mm from volts, amps and travel speed — with process efficiency. The calculation implements HI = η·V·I·60 / (1000·S) (ISO/TR 17671; AWS D1.1 Annex). Heat input drives cooling rate, hardness and distortion. Typical structural windows: 1–2.5 kJ/mm. Quenched-and-tempered steels cap it hard (over-soften); duplex stainless caps both ends.
How to use Welding Heat Input Calculator
- 1Enter Arc voltage in V.
- 2Enter Welding current in A.
- 3Enter Travel speed in mm/min.
- 4Enter Process efficiency (SMAW 0.8 · GMAW 0.8 · GTAW 0.6 · SAW 1.0 (ISO/EN factors)).
- 5Read Heat input instantly — no submit button needed.
- 6Need US units? Flip the SI/Imperial toggle and every field converts.
Why use Welding Heat Input Calculator?
- ✓Implements the standard formula — HI = η·V·I·60 / (1000·S)
- ✓Reference cited on-page: ISO/TR 17671; AWS D1.1 Annex
- ✓One-click SI ⇄ Imperial toggle — values convert in place, physics stays in SI
- ✓Live worked example: the substitution recomputes from your numbers
- ✓Runs entirely in your browser — nothing uploaded, free forever
Frequently asked questions
What formula does the Welding Heat Input Calculator use?+
It computes HI = η·V·I·60 / (1000·S), per ISO/TR 17671; AWS D1.1 Annex. The formula is displayed under the result along with a worked example substituted with your own inputs.
What should I keep in mind when using this calculator?+
Heat input drives cooling rate, hardness and distortion. Typical structural windows: 1–2.5 kJ/mm. Quenched-and-tempered steels cap it hard (over-soften); duplex stainless caps both ends.
Does this follow AWS/IS welding codes?+
Each tool implements the formula from the cited code or handbook (AWS D1.1, IS 800, ISO/EN). Qualified WPS values always govern over any calculator for code work.
Is the Welding Heat Input Calculator free to use?+
Yes — completely free, no sign-up, no limits. It runs client-side in your browser, so inputs stay private and results are instant even on slow connections.
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