Shielding Gas Consumption Calculator

Gas used equals flow rate in CFH times welding time in hours, so the minutes you enter are divided by 60 first. At 35 CFH, one full hour of arc time uses exactly 35 cubic feet. It is a straight ratio that assumes steady flow.

Cylinder duration in hours equals cylinder capacity in cubic feet divided by the flow rate in CFH. A 250 cu ft bottle at 35 CFH gives about 7.14 hours of continuous arc, while an 80 cu ft bottle at 40 CFH gives exactly 2 hours.

Yes. Flow rate is always required, but welding time and cylinder size are optional. Any output whose input you leave blank simply shows a dash instead of a number, so you can compute just gas used, just run time, or both together.

It is arc-on time, the minutes gas is actually flowing through the torch. A real shift adds setup, tacking, grinding and idle periods, so a cylinder lasts far more wall-clock time than the pure arc-on figure suggests.

Imperial gas units throughout: flow in cubic feet per hour (CFH), cylinder size in cubic feet, and duration in hours. If your flowmeter reads litres per minute you need to convert before entering values, since the tool does not accept metric flow.

The result is an exact division carried to nine decimal places, so 250 divided by 35 displays as 7.142857143 hours rather than a rounded figure. Round it yourself to whatever precision your job planning needs.

Many MIG jobs run around 20 to 40 CFH and TIG around 10 to 25 CFH, higher with larger cups or in a draft. Always use the value from your welding procedure or flowmeter rather than a generic figure for an accurate estimate.

Leaks at fittings, long pre-flow and post-flow, drafts that force higher flow, and the surge at arc start all consume extra gas the calculation does not model. Check connections and set the flowmeter to the lowest rate that still gives clean, porosity-free welds.

Yes. The calculation runs entirely in your browser and nothing is uploaded, so your flow rates and job figures never leave your device.