How do I convert miles per hour to kilometers per hour?

To convert mph to kmh, multiply the mph value by 1.609344. For example, 60 mph = 60 × 1.609344 = 96.56 kmh. This is the standard conversion factor used worldwide.

What is a knot in speed measurement?

A knot is a unit of speed equal to one nautical mile per hour, approximately 1.151 mph or 1.852 kmh. It's commonly used in aviation and maritime navigation.

How many meters per second is 1 mph?

1 mph equals 0.44704 meters per second. To convert mph to m/s, multiply by 0.44704. This conversion is useful for physics and engineering calculations.

What is the difference between speed and velocity?

Speed is the rate of distance traveled over time (scalar), while velocity includes both speed and direction (vector). This converter handles speed conversions between different units.

Are these speed conversions accurate for scientific use?

Yes, our converter uses precise conversion factors defined by international standards. It's suitable for scientific, engineering, and professional applications requiring accurate speed conversions.

Speed Converter

Convert between mph, km/h, m/s, knots, Mach and more with instant results and high precision. Perfect for automotive, aviation, marine navigation, and physics calculations.

Speed Conversion Calculator

Convert between metric and imperial speed units with high precision

From

Decimal Places: 6

Key Features

Instant conversion between metric and imperial speed units

High precision calculations with adjustable decimal places

Supports automotive, aviation, marine, and scientific applications

Live conversion examples and unit swapping

Understanding Speed

Common Units: km/h (metric), mph (imperial), m/s (scientific), knots (navigation)

Base Conversions: 1 m/s = 3.6 km/h, 1 mph = 1.609 km/h, 1 knot = 1.852 km/h

Mach Number: Speed relative to sound (~343 m/s at sea level, varies with temperature)

Nautical Miles: Based on Earth's circumference (1' latitude = 1 nautical mile)

Tips & Strategies

Aviation Use: Always use knots for flight planning and navigation - it's the international standard

Marine Navigation: Knots are standard for boats and ships worldwide for consistency

Scientific Work: Use m/s for physics calculations and research publications

Quick Mental Math: 60 mph ≈ 100 km/h, 100 km/h ≈ 28 m/s, 1 m/s ≈ 2.2 mph

Precision Guidelines: Use 0-1 decimals for driving, 2-3 for aviation, 4+ for scientific work

Temperature Effects: Speed of sound varies with temperature - Mach calculations need altitude/temp data

Frequently Asked Questions

What is a knot and why is it used in aviation and marine?

A knot is one nautical mile per hour. Since nautical miles are based on the Earth's circumference (1 nautical mile = 1 minute of latitude), knots provide a natural reference for navigation on Earth's surface.

How fast is the speed of sound (Mach 1)?

The speed of sound varies with temperature and altitude. At sea level and 20°C (68°F), Mach 1 is approximately 343 m/s, 1,235 km/h, or 767 mph. Aircraft flying faster than this are supersonic.

Why do different countries use different speed units?

Historical development of measurement systems. Most countries use km/h (metric system), while the US, UK, and a few others use mph (imperial system). Aviation uses knots internationally.

How accurate should speed measurements be?

For everyday driving, 1 km/h or 1 mph precision is sufficient. Aviation and marine navigation may require higher precision (0.1 knots). Scientific applications might need even greater accuracy.

What's the difference between speed and velocity?

Speed is a scalar quantity (magnitude only), while velocity is a vector quantity (magnitude and direction). In everyday usage, these terms are often used interchangeably.

How do I convert between metric and imperial speeds?

Key conversions: 1 mph = 1.609 km/h, 1 m/s = 3.6 km/h, 1 knot = 1.852 km/h. Quick estimate: 60 mph ≈ 100 km/h for mental calculations.

When should I use each speed unit?

Use km/h for road speeds (metric countries), mph for US/UK roads, m/s for physics/science, knots for aviation/marine navigation, and Mach for supersonic applications.