Airspeed Calculator

Convert between IAS, TAS, CAS, and groundspeed — with density altitude corrections.

Calculator Aviation Updated Apr 19, 2026
How to Use
  1. Enter IAS and pressure altitude.
  2. TAS is computed for the given temperature.
Inputs
Result

Definitions

IAS
Indicated Airspeed — what the instrument reads
CAS
IAS corrected for instrument and position error
TAS
True airspeed — CAS corrected for density
GS
Ground speed — TAS ± wind component
Rule of thumb
TAS ≈ IAS × (1 + 0.02 · alt_kft)

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