Use this calculator for flight-planning study or a first-pass cross-check when all inputs describe the same aircraft, atmospheric condition, and phase of flight.

Trip fuel (kg)

Fuel planned for the route.

Contingency percentage (%)

Allowance percentage; five percent is a common planning figure and twenty is a typical ceiling.

Compute the contingency allowance as a percentage of the planned trip fuel. The tool evaluates the supplied inputs together and returns the named outputs below; it does not infer omitted operating conditions or change the units shown.^[1]

Contingency fuel (kg)

Contingency fuel allowance.

• Do not use a generic calculator in place of the current aircraft flight manual, approved performance data, operating limitations, NOTAMs, weather, or regulations. Real performance changes with configuration, runway condition, altitude, temperature, wind, loading, and technique.
• Use finite inputs in the displayed units and preserve more precision than the final presentation requires. Independently verify safety-critical, financial, compliance, or production decisions.

Cross-check the result against the aircraft flight manual or approved planning system, then apply the required safety margins. Keep signed wind, heading, altitude, speed, and fuel conventions explicit.

• Contingency Fuel Calculator

  Compute the contingency fuel allowance as a percentage of trip fuel.

• Minimum Fuel Required

  Add planned trip, alternate, contingency, and final-reserve fuel in one consistent unit, then show the margin against fuel on board. It does not substitute for route-specific regulations or aircraft performance planning.

• Basic Block Fuel Subtotal Calculator

  Sum taxi, trip, contingency, and final-reserve components into a basic block-fuel subtotal; other required fuel may still apply.