RPM to Linear Velocity Calculator
Enter the RPM and the radius or diameter to find the surface (linear) speed. The tool returns m/s, km/h and the circumference for wheels, pulleys and CNC work.
How to convert RPM to linear velocity
- Enter the rotational speed in RPM.
- Enter the radius, or switch to diameter, in metres.
- Read the surface speed in m/s and km/h.
Examples
Wheel at 1000 RPM
rpm = 1000, radius = 0.1 m
10.47 m/s (37.70 km/h)
Pulley by diameter
rpm = 300, diameter = 0.5 m
7.85 m/s
Frequently asked questions
How do I convert RPM to linear speed?
Multiply the circumference (2 x pi x radius) by the RPM and divide by 60. That gives the surface speed in metres per second.
What is the difference between radius and diameter input?
Diameter is twice the radius. If you enter a diameter, the tool halves it first, then uses 2 x pi x radius for the circumference.
Why does the tool show km/h as well?
Surface speed in km/h is often easier to picture. It is simply the m/s value multiplied by 3.6.
Is this the same as tangential speed?
Yes. The surface speed of a point on the rim is its tangential speed, the distance it travels along its circular path each second.
What can I use this for?
Wheels and tyres, conveyor and timing belts, pulleys, rollers and CNC or lathe surface speeds all relate RPM and radius to linear speed.
Related tools
Angular Velocity Calculator
Convert between RPM, rad/s and deg/s, and find tangential speed from a radius. Enter rpm or radians per second to relate every rotational measure.
Centripetal Force Calculator
Find centripetal force and acceleration for circular motion from mass, radius and speed. Enter linear speed or angular velocity to get force in newtons.
Speed Distance Time Calculator
Work out speed, distance or time from the other two with speed = distance / time. Supports m/s, km/h and mph, plus metres, kilometres and miles.
555 Timer Calculator
Calculate 555 timer astable frequency, period, high and low times and duty cycle from R1, R2 and the timing capacitor. Free oscillator design helper.
Absolute Humidity Calculator
Calculate absolute humidity in grams of water vapor per cubic meter from air temperature and relative humidity. Fast, free and works in your browser.
Allele Frequency Calculator
Find allele frequencies from genotype counts. Enter the number of AA, Aa and aa individuals to get the A and a allele frequencies and allele totals.