Fuel Flow from AFR Calculator
Reviewed by Hamza Gujjar, Algorithm Architect & Software Developer
Last updated: July 27, 2026
📚 Confused about how this is calculated? Read the full Using This Calculation Backward to Catch a Fuel Leak or Meter Fault →
Working backward from air flow to fuel flow
Air flow is often the easier quantity to measure directly using an anemometer or duct flow meter on the combustion air supply - this calculator lets you infer or cross-check fuel flow against a target air-fuel ratio without measuring fuel flow directly.
Worked example
For 1,000 kg/hr of air flow at a 14.7 air-fuel ratio:
Fuel Flow = 1000 / 14.7 = 68.0272 kg/hr fuel flow
This calculation is especially useful for quick field verification - if measured fuel flow differs meaningfully from this calculated value, it can indicate a combustion tuning issue, sensor drift, or a genuine deviation from the intended air-fuel ratio worth investigating further.