Aviation Speed Converter
Convert between aviation speed units: Knots, MPH, km/h, and Mach number
Aviation Speed Converter
Convert between aviation speed units: Knots, MPH, km/h, and Mach number
°C
ISA sea level: 15°C • Used for accurate Mach calculation
661.48 knots|1,225.05 km/h|340.29 m/s
Additional Units
Meters per Second0 m/s
Feet per Minute0 ft/min
True Airspeed (TAS)0 kt
Quick Reference
Typical light aircraft cruise
Typical GA cruise speed
Below 10,000 ft limit (FAA)
High-speed turboprop
Understanding Aviation Speed Units
- Knots (kt): Standard aviation unit. 1 knot = 1 nautical mile per hour = 1.852 km/h
- Mach Number: Ratio of aircraft speed to speed of sound. Varies with temperature.
- TAS vs IAS: This converter calculates True Airspeed (TAS). Indicated Airspeed (IAS) varies with altitude and temperature.
Important Speed Limits
- Below 10,000 ft MSL (Class B, C, D, E): 250 KIAS maximum (FAR 91.117)
- Within 4 NM of primary Class C/D airport: 200 KIAS maximum
- VNE (Never Exceed Speed): Aircraft-specific maximum speed
- VMO/MMO: Maximum Operating Speed (IAS) / Mach Number
Technical Details & Formulas
Speed Conversions:
• 1 knot = 1.852 km/h (exact, by definition)
• 1 knot = 1.15077945 mph
• 1 mph = 1.60934 km/h
Speed of Sound:
• a = √(γ × R × T) where γ=1.4, R=287.05 J/(kg·K)
• At ISA sea level (15°C): a ≈ 340.29 m/s ≈ 661.47 kt
• Temperature decreases ~2°C per 1000 ft in troposphere
Mach Number:
• M = TAS / a (True Airspeed / Speed of Sound)
• Subsonic: M < 1.0
• Transonic: M ≈ 0.8 to 1.2
• Supersonic: M > 1.0
IMPORTANT: The values and information shown on this page are for educational purpose and reference only. You are solely responsible for verifying all data and ensuring the correct official information is acquired.