QuikCalcTools

Speed Converter 2025

km/h to mph - Velocity Converter

🏎️ Universal Speed Converter

✓ 10 Speed Units - km/h, mph, m/s, knots

✓ Real-time Conversion - All units update instantly

✓ Speed Context - Walking to supersonic

✓ Vehicle Speeds - Car, train, plane

🛣️ Highway Speed

Normal driving

100.0 km/h

62.1 mph

27.78 m/s

Convert Speed

Speed Info & Presets

Current Speed

100.0 km/h

62.1 mph

27.78 m/s

54.0 knots

Quick Conversions

km/h:100.0 km/h
mph:62.1 mph
m/s:27.78 m/s
Knots:54.0 kn

Conversion Formulas

km/h → mph: km/h × 0.621371
mph → km/h: mph × 1.60934
m/s → km/h: m/s × 3.6
km/h → m/s: km/h ÷ 3.6

Quick Speed Presets

Speed Conversion Table

km/hmphm/sKnots
10 km/h6.2 mph2.78 m/s5.4 kn
20 km/h12.4 mph5.56 m/s10.8 kn
50 km/h31.1 mph13.89 m/s27.0 kn
80 km/h49.7 mph22.22 m/s43.2 kn
100 km/h62.1 mph27.78 m/s54.0 kn
120 km/h74.6 mph33.33 m/s64.8 kn
200 km/h124.3 mph55.56 m/s108.0 kn
300 km/h186.4 mph83.33 m/s162.0 kn

What is Speed Conversion?

Speed conversion transforms velocity measurements between metric (km/h, m/s) and imperial (mph, ft/s) systems, plus nautical (knots) and aviation (Mach) units. Essential for travel, sports, physics, and vehicle specifications.

Our converter supports 10 speed units including km/h, mph, m/s, knots, Mach, and more. Get real-time conversion across all units with speed context. Perfect for speed limits, running pace, flight speeds, and physics calculations.

How to Use

  1. 1Enter speed value in any unit field
  2. 2All other units update automatically in real-time
  3. 3See speed context (walking, driving, flying, etc.)
  4. 4View vehicle speed comparisons
  5. 5Use quick presets for common speeds

Speed Conversion Formulas

km/h ⇄ mph

km/h to mph:

mph = km/h × 0.621371

Example: 100 km/h = 100 × 0.621 = 62.1 mph

mph to km/h:

km/h = mph × 1.60934

Example: 60 mph = 60 × 1.609 = 96.6 km/h

km/h ⇄ m/s

km/h to m/s:

m/s = km/h ÷ 3.6

Example: 100 km/h = 100 ÷ 3.6 = 27.78 m/s

m/s to km/h:

km/h = m/s × 3.6

Example: 25 m/s = 25 × 3.6 = 90 km/h

km/h to mph Conversion Table

km/hmphm/sKnots
10 km/h6.2 mph2.78 m/s5.4 kn
20 km/h12.4 mph5.56 m/s10.8 kn
50 km/h31.1 mph13.89 m/s27 kn
80 km/h49.7 mph22.22 m/s43.2 kn
100 km/h62.1 mph27.78 m/s54 kn
120 km/h74.6 mph33.33 m/s64.8 kn
200 km/h124.3 mph55.56 m/s108 kn
300 km/h186.4 mph83.33 m/s162 kn

Speed Units Explained

🌍 Metric System

m/s: Meters per second (SI unit)
km/h: Kilometers per hour
km/s: Kilometers per second

🌍 Used worldwide for speed

🇺🇸 Imperial System

mph: Miles per hour
ft/s: Feet per second
mi/s: Miles per second

🇺🇸 Used in United States

✈️ Special Units

Knot: Nautical miles/hour (1.852 km/h)
Mach: Speed of sound (~343 m/s)
c: Speed of light (299,792,458 m/s)

✈️ Aviation & marine use

Common Speed Measurements

🚶 Human Speeds

  • Slow walk: 3 km/h (1.9 mph)
  • Average walk: 5 km/h (3.1 mph)
  • Fast walk: 7 km/h (4.3 mph)
  • Jogging: 10 km/h (6.2 mph)
  • Running: 15 km/h (9.3 mph)
  • Sprinting: 25-30 km/h (15.5-18.6 mph)
  • Usain Bolt (record): 44.7 km/h (27.8 mph)

🚗 Vehicle Speeds

  • Bicycle: 15-25 km/h (9-15 mph)
  • City driving: 30-50 km/h (19-31 mph)
  • Highway: 100-120 km/h (62-75 mph)
  • Sports car: 250+ km/h (155+ mph)
  • F1 car: 350 km/h (217 mph)
  • Bullet train: 320 km/h (199 mph)
  • Maglev train: 600 km/h (373 mph)

✈️ Aircraft Speeds

  • Small plane: 200 km/h (124 mph)
  • Commercial jet: 850-950 km/h (528-590 mph)
  • Fighter jet: 2,000+ km/h (1,243+ mph)
  • Concorde: 2,180 km/h (1,354 mph)
  • SR-71 Blackbird: 3,540 km/h (2,200 mph)
  • Space Shuttle: 28,000 km/h (17,400 mph)

🌍 Speed Limits

  • School zone: 25-30 km/h (15-19 mph)
  • Residential: 40-50 km/h (25-31 mph)
  • City streets: 50-60 km/h (31-37 mph)
  • Rural roads: 80-100 km/h (50-62 mph)
  • Highway (US): 100-120 km/h (65-75 mph)
  • Autobahn (Germany): No limit (some sections)

Frequently Asked Questions

1. How do I convert km/h to mph?

To convert km/h to mph, multiply by 0.621371. For quick mental math, multiply by 0.6.

Common Conversions:

50 km/h = 31 mph
80 km/h = 50 mph
100 km/h = 62 mph
120 km/h = 75 mph

2. What is a knot in speed?

A knot is one nautical mile per hour, equal to 1.852 km/h or 1.151 mph. Used in maritime and aviation.

Knot Conversions:

10 knots18.5 km/h (11.5 mph)
50 knots92.6 km/h (57.5 mph)
100 knots185.2 km/h (115.1 mph)

3. What is Mach speed?

Mach is the ratio of speed to the speed of sound. Mach 1 = speed of sound (~343 m/s or 1,235 km/h at sea level).

Mach Numbers:

Subsonic: Below Mach 1 (e.g., commercial jets)
Mach 1: 1,235 km/h (767 mph) - Speed of sound
Supersonic: Mach 1-5 (e.g., fighter jets)
Hypersonic: Above Mach 5 (e.g., space vehicles)

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