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.

Pressure altitude (ft)

Pressure altitude within the troposphere (up to about 36,089 ft).

Compute the ISA static pressure at a given pressure altitude in the troposphere. 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]

Pressure (hPa)

ISA static pressure.

• 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.

• Field Elevation Pressure Calculator

  Compute the ISA static pressure in hectopascals at a given field elevation.

• ISA Pressure at Altitude Calculator

  Compute ISA standard pressure for a geopotential altitude through the troposphere and lower stratosphere.

• ISA Standard Temperature Calculator

  Compute the ISA standard temperature for a given altitude in the troposphere.