Physics overview
What is RPM?
RPM means revolutions per minute. It measures how many complete rotations an object makes in one minute.
Formula
RPM conversion formulas
Rotational SpeedRPM = 60f
- RPM is revolutions per minute.
- f is rotational frequency in hertz.
- ω is angular velocity in radians per second.
Worked example
Convert 2 Hz to RPM
- Write the formula: RPM = 60f.
- Substitute the frequency: RPM = 60 × 2.
- Calculate the speed: RPM = 120.
Conversion equations
Convert RPM, hertz, and rad/s
Rotational frequency
f = RPM ÷ 60
Divide RPM by 60 to obtain hertz.
Angular velocity
ω = 2π × RPM ÷ 60
Convert RPM to revolutions per second, then multiply by 2π.
Physical relationship
RPM and rotational frequency
One hertz equals one revolution per second, which equals 60 RPM. RPM therefore increases directly with rotational frequency.
Units
Standard rotational units
Use RPM for revolutions per minute, hertz for revolutions per second, and radians per second for angular velocity.
Real-world applications
Where RPM is used
- Electric motors and generators.
- Vehicle engines and drive shafts.
- Fans, pumps, and turbines.
- Drills and machining equipment.
- Rotating laboratory equipment.
Calculation guidance
Important input rules
- Enter positive finite values only.
- Frequency must be entered in hertz.
- Angular velocity must be entered in radians per second.
- Rotation direction is not represented.
- Degrees per second are not converted automatically.
Related tools
Continue your rotational analysis
Use the Rotational Frequency Calculator to calculate frequency, angular velocity, or rotation period.
Use the Angular Velocity Calculator to calculate angular velocity, displacement, or time.
Questions and answers
RPM calculator FAQ
What formula does the RPM calculator use?
It uses RPM = 60f, where revolutions per minute equals rotational frequency in hertz multiplied by 60.
How do you convert RPM to hertz?
Divide RPM by 60. For example, 120 RPM equals 2 hertz.
How do you convert RPM to angular velocity?
Use ω = 2π × RPM / 60 to convert revolutions per minute to radians per second.
What units does the RPM calculator use?
Rotational speed is measured in RPM, rotational frequency in hertz, and angular velocity in radians per second.