The Global Speed Conversion Guide
Speed is a measure of how fast an object moves. However, the units used to measure speed vary drastically depending on where you are and what vehicle you are operating. From the kilometers per hour (km/h) used on European highways to the knots (kn) used by sailors and pilots, our converter helps you navigate these differences effortlessly.
Driving Abroad: km/h vs. mph
This is the most critical conversion for travelers. Mistaking one for the other can lead to speeding tickets or accidents.
- USA & UK: Use Miles per Hour (mph).
- Canada, Australia, Europe: Use Kilometers per Hour (km/h).
- Conversion: 1 mph ≈ 1.61 km/h.
So, 60 mph ≈ 100 km/h.
What is a "Knot" (kn)?
The Knot is a unit of speed used strictly in maritime (ships) and aviation (planes) contexts. It is defined as one Nautical Mile per hour.
- Origin: Sailors used to throw a wooden log attached to a rope with knots tied at regular intervals into the water. They would count how many knots unspooled in a specific time to calculate the ship's speed.
- Value: 1 Knot ≈ 1.15 mph or 1.852 km/h.
Frequently Asked Questions (FAQ)
How fast is Mach 1?
Mach 1 represents the speed of sound. At sea level and standard temperature (20°C), Mach 1 is approximately 1,235 km/h (767 mph). Speeds above this are considered "supersonic."
What is the speed of light?
The speed of light in a vacuum is exactly 299,792,458 meters per second (approx. 300,000 km/s). It is the universal speed limit according to Einstein's theory of relativity.
Disclaimer: Speed limits displayed on road signs are legally binding. Always check local traffic laws when driving in a new country.