Speed Converter

Result: 1 meter/second = 3.6 kilometer/hour

Choose a unit on the left (From). The list on the right shows how much 1 From unit equals in every other unit — just like a reference Speed Converter.

Quick tips

  • Enter the value you want to convert in the From box.
  • Select the source unit on the left and the target unit on the right.
  • Open the scientific calculator when you need to calculate a speed before converting, then click “Use result in From”.

How this speed converter works

This Speed Converter uses meter per second (m/s) as its internal base unit. Your input is first converted into m/s using high-precision factors, then divided by the factor for the target unit. The right-hand list shows how much 1 From unit equals in every other unit so you can scan all equivalents at once.

Common conversion facts

  • 1 m/s = 3.6 km/h
  • 1 km/h ≈ 0.27778 m/s
  • 1 mph ≈ 0.44704 m/s
  • 1 knot ≈ 0.514444 m/s

Why use an online speed converter?

A dedicated speed converter is useful whenever you move between driving speeds, aircraft speeds, maritime knots, scientific velocities or Mach numbers. Cars and road signs often use km/h, aviation materials use knots, and physics textbooks prefer m/s. Instead of memorising factors like “mph to km/h”, this page lets you select a unit once and instantly see all equivalents.

The converter is designed for people who work with real-world speeds as well as scientific scenarios. You can convert everyday values such as 120 km/h into mph, and also compare them with reference values like the speed of sound or the speed of light. If you need to calculate a custom expression first, open the built-in scientific calculator, evaluate the formula, and send the result directly into the “From” box.

Popular speed conversions you can do here

  • m/s to km/h and km/h to m/s for physics homework or engineering projects.
  • km/h to mph when reading car reviews or converting international speed limits.
  • Knots to mph or km/h for aviation, sailing and marine navigation.
  • Mach to m/s or mph when dealing with aircraft performance and sonic speeds.
  • Comparing everyday speeds with constants such as Earth’s orbital velocity or the speed of light.

How to read the right-hand list of units

The left list controls which unit you are converting from. When you click any entry, the list on the right is refreshed to show how much 1 of that unit equals in every other unit in the database. For example, if you select “kilometer/hour [km/h]” on the left, the right list will show values such as:

  • 1 km/h ≈ 0.27778 meter/second
  • 1 km/h ≈ 0.62137 mile/hour
  • 1 km/h ≈ 0.53996 knot
  • …and many more conversions.

This “reference table” style matches traditional engineering converters and makes it easy to see relationships between units without running multiple separate calculations.

Physical constants and special speeds

In addition to everyday units, this converter includes several important physical velocities:

  • Velocity of light in vacuum — about 299,792,458 m/s.
  • Cosmic velocities — first, second and third cosmic velocities used in orbital mechanics.
  • Earth’s orbital velocity — roughly 29.78 km/s around the Sun.
  • Velocity of sound in water and sea water — useful in underwater acoustics.
  • Mach numbers — based on the speed of sound at specified conditions.

These values let you compare the scale of everyday speeds with extreme or astrophysical velocities in a single place.

Tips for using this converter effectively

  • Keep the From value simple. Use the calculator icon for formulas such as distance/time before converting.
  • Check whether you need knots or mph. Nautical and aviation charts almost always use knots, not mph.
  • Use SI units for scientific work. For physics and engineering, m/s and km/s are usually preferred.
  • Copy results into other tools. You can combine this page with the distance & time tools when planning trips or simulations.

Who benefits from this speed converter?

  • Students practising unit conversions in physics or engineering courses.
  • Drivers and travellers converting speed limits or navigation systems between km/h and mph.
  • Pilots and sailors working with knots, Mach numbers and reference speeds.
  • Researchers and hobbyists comparing real-world speeds with orbital or relativistic values.

Final note

This speed converter is intended for general planning and education. For safety-critical use (aviation, marine navigation, automotive testing or industrial processes) always follow official manuals and certified instruments. For quick everyday conversions, this page gives you a fast, reliable and distraction-free way to move between any common speed or velocity unit.