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Imperial Speed Unit Converter

Feet Per Second Calculator

Convert between feet per second (fps), miles per hour (mph), kilometers per hour (km/h), and meters per second (m/s). Essential for physics, ballistics, and engineering.

Quick Conversion Factors
1 fps = 0.682 mph = 1.097 km/h
1 mph = 1.467 fps = 0.447 m/s
1 m/s = 3.281 fps = 2.237 mph
1 km/h = 0.911 fps = 0.278 m/s

FPS Converter

Enter a value and select the input unit

Common Speeds in Feet Per Second

SpeedFPSMPHContext
Human walking3 fps2.0 mphAverage walking pace
Human running15 fps10.2 mphJogging speed
Usain Bolt max22 fps15.0 mphWorld record sprint
City driving (30 mph)44 fps30.0 mphUrban speed limit
Highway (60 mph)88 fps60.0 mphTypical highway speed
Baseball fastball120 fps81.8 mphProfessional pitcher
100 mph147 fps100.2 mphHigh-speed driving
Bullet train400 fps272.7 mphHigh-speed rail
Commercial jet700 fps477.3 mphCruising speed
Speed of sound1125 fps767.0 mphMach 1 at sea level
Rifle bullet2200 fps1500.0 mphHigh-velocity round
Orbital velocity25000 fps17045.5 mphISS orbital speed

Understanding Feet Per Second

Feet per second (fps or ft/s) is an imperial unit of speed measuring how many feet an object travels in one second. It's commonly used in:

  • Ballistics - Measuring bullet and projectile velocities
  • Physics - Calculating motion in imperial units
  • Engineering - Fluid dynamics and mechanical systems
  • Sports - Baseball pitch speed, golf ball speed
  • Aviation - Some airspeed calculations

The unit provides finer granularity than mph for short-distance measurements and is the imperial equivalent of meters per second (m/s).

Conversion Formulas

FPS to MPH
mph = fps × 0.681818

or fps ÷ 1.46667

MPH to FPS
fps = mph × 1.46667

or mph ÷ 0.681818

FPS to M/S
m/s = fps × 0.3048

Since 1 foot = 0.3048 meters

M/S to FPS
fps = m/s × 3.28084

or m/s ÷ 0.3048

Frequently Asked Questions

Common questions about feet per second conversions

How do you convert feet per second to mph?

To convert feet per second (fps) to miles per hour (mph), multiply by 0.681818. For example, 100 fps × 0.681818 = 68.18 mph.

What is 100 feet per second in mph?

100 feet per second equals 68.18 mph (miles per hour). This is slightly above typical highway speed limits.

How fast is the speed of sound in feet per second?

The speed of sound in air at sea level and 20°C is approximately 1,125 feet per second (343 meters per second or 767 mph). This is known as Mach 1.

Why use feet per second instead of mph?

Feet per second is commonly used in physics, ballistics, and engineering because it provides finer granularity for measuring short-distance speeds. It's also the imperial equivalent of meters per second (m/s).