Speed Converter

Convert between different units of speed and velocity - km/h, mph, m/s, knots, and more.

Result: 0.0000

What It Does

A Speed Converter is an essential tool for converting between different units of speed and velocity. It converts between metric units like meters per second (m/s) and kilometers per hour (km/h), and imperial units such as miles per hour (mph) and feet per second (ft/s), as well as specialized units like knots (nautical miles per hour). This tool is perfect for travelers understanding speed limits in different countries, athletes tracking running or cycling speeds, pilots and sailors working with knots, scientists calculating velocities, and anyone needing to convert speed measurements. It provides accurate conversions with real-time updates, supporting both metric (SI) and imperial systems. Essential for understanding vehicle speeds, wind speeds, athletic performance, and any velocity-related calculations.

Key Features:

  • Convert between 5 common speed units (meters/second, kilometers/hour, miles/hour, feet/second, knots)
  • Real-time conversion as you type - instant results
  • Swap button to quickly reverse conversion direction
  • High precision results with up to 4 decimal places
  • Support for both metric and imperial speed systems
  • Knots support for aviation and maritime applications
  • Clear unit labels with standard abbreviations
  • Mobile-responsive design for on-the-go conversions

How To Use

Convert speeds instantly between metric and imperial units. Perfect for travel, sports, aviation, and physics calculations.

1

Enter the Speed Value

Type or paste the speed value you want to convert into the "Value" input field. You can enter whole numbers or decimals (e.g., 100, 65.5, 0.75).

2

Select Source Unit

Choose the unit you're converting FROM using the "From" dropdown. Options include meters/second, kilometers/hour, miles/hour, feet/second, and knots.

3

Select Target Unit

Choose the unit you want to convert TO using the "To" dropdown. The result updates automatically as you make your selection.

4

View Result

See the converted speed value displayed prominently in the result box. The conversion happens in real-time as you type or change units.

5

Swap Units (Optional)

Click the swap button (⇄) to instantly reverse the conversion direction, swapping the "From" and "To" units without re-entering the value.

Pro Tips

  • •1 km/h = 0.621371 mph (approximately 0.62 mph)
  • •1 mph = 1.60934 km/h (approximately 1.61 km/h)
  • •1 knot = 1.15078 mph = 1.852 km/h
  • •1 m/s = 3.6 km/h = 2.237 mph
  • •Speed limits vary by country - convert to understand local limits
  • •Knots are standard for aviation and maritime speeds

Benefits

Travel: Understand speed limits and vehicle speeds in different countries
Sports: Convert running, cycling, and athletic speeds between units
Aviation: Convert between knots, mph, and km/h for flight planning
Science: Calculate velocities in physics and engineering applications
Education: Learn speed relationships between different unit systems
Accuracy: Eliminate manual calculation errors in speed conversions
Time Saving: Instant conversions save time over manual calculations
Versatility: Handle all common speed units in one tool

Use Cases

Travel and Driving

Convert speed limits and vehicle speeds when traveling internationally. Understanding speed limits in different units helps ensure safe and legal driving.

Convert 120 km/h speed limit to mph (74.56 mph) when driving in Europe

Athletics and Sports

Convert running, cycling, and athletic speeds for training and competition. Athletes and coaches often work with different speed units.

Convert a 5-minute mile pace to km/h (19.31 km/h) for training metrics

Aviation and Maritime

Convert speeds for flight planning and navigation. Pilots and sailors work with knots, while ground speeds may be in mph or km/h.

Convert 150 knots to mph (172.62 mph) for flight planning

Physics and Engineering

Calculate velocities in scientific and engineering applications. Scientists often need to convert between m/s, km/h, and other units.

Convert 10 m/s to km/h (36 km/h) for physics calculations

Weather and Wind Speed

Convert wind speeds between different measurement systems. Meteorologists and weather services use various units.

Convert 25 mph wind speed to km/h (40.23 km/h) for weather reports

Frequently Asked Questions

1 What is a knot and why is it used?
A knot is a unit of speed equal to one nautical mile per hour. One knot equals 1.15078 miles per hour or 1.852 kilometers per hour. Knots are used in aviation and maritime navigation because nautical miles are based on the Earth's latitude (1 nautical mile = 1 minute of latitude), making them convenient for navigation. The term "knot" comes from the historical method of measuring ship speed using a knotted rope.
2 How do I convert km/h to mph?
To convert kilometers per hour to miles per hour, multiply by 0.621371. For example, 100 km/h × 0.621371 = 62.1371 mph. Conversely, to convert mph to km/h, multiply by 1.60934. For example, 60 mph × 1.60934 = 96.5604 km/h. Our converter handles this automatically with high precision.
3 What is meters per second used for?
Meters per second (m/s) is the SI (International System of Units) base unit for speed. It's commonly used in physics, engineering, and scientific applications. One m/s equals 3.6 km/h or 2.237 mph. It's particularly useful for scientific calculations because it's the standard unit in physics equations and provides a direct relationship to distance (meters) and time (seconds).
4 Are speed conversions always exact?
Speed conversions use precise conversion factors based on international standards. However, some conversions between metric and imperial systems involve irrational numbers, so results are approximations rounded to the specified precision (typically 4 decimal places). For all practical purposes, this level of accuracy is more than sufficient for travel, sports, and most applications.
5 Why do different countries use different speed units?
Most of the world uses kilometers per hour (km/h) as part of the metric system, while the United States, Liberia, and Myanmar primarily use miles per hour (mph). This historical difference stems from when countries adopted the metric system. The United States has not fully adopted the metric system for everyday use, though it's used in science and some industries. This is why speed converters are essential for international travel and communication.
6 Can I convert very high speeds like aircraft or spacecraft?
Yes, the converter handles any speed value, including very high speeds. However, for speeds approaching the speed of light, relativistic effects become significant and simple unit conversion may not be sufficient for precise scientific calculations. For all practical speeds (vehicles, aircraft, etc.), the converter provides accurate results.

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