Speed Converter

Convert any speed between metric, imperial and nautical units. Mach is included using the speed of sound at sea level in standard conditions, which the tool states clearly.

How to use the Speed Converter

1. Type the speed value.
2. Choose the unit it is in, such as km/h.
3. Choose the unit you want, such as mph or knots.
4. Copy the result or check the table for all units.

Features

• km/h, mph, m/s, knots, ft/s and Mach
• Exact knot definition (1,852 m per hour)
• Mach based on 340.294 m/s at sea level, 15 °C
• Live conversion as you type

Benefits

• Understand speed limits and car specs abroad
• Convert wind speeds for sailing and flying
• Handy for physics homework

Frequently asked questions

How do I convert km/h to mph?

Divide by 1.609344. For example, 100 km/h is about 62.14 mph.

Why does Mach depend on altitude?

Mach is a ratio to the local speed of sound, which falls as air gets colder. This tool uses the standard sea-level value of 340.294 m/s.

What is a knot?

One knot is one nautical mile per hour, which is exactly 1.852 km/h.

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