Frequency & RPM Converter

Convert frequency values across 22 units instantly — the full SI ladder from nanohertz to quettahertz (nHz, µHz, mHz, Hz, kHz, MHz, GHz, THz, PHz, EHz, ZHz, YHz, RHz, QHz), plus angular and rotational units used in motors, drives, and mechanical systems (rad/s, rpm, rps, rph, rpd, rpwk, rpmo, rpy). Enter a value from a meter reading, datasheet, oscillator spec, or motor nameplate, and see it converted across every supported unit at once — grouped into SI Frequency Units and Angular & Rotational Units for quick scanning. Results include the exact formula used, a side-by-side waveform comparison chart so students and hobbyists can see how frequency changes visually, and a quick reference table for common values. Built for electricians, RF and audio engineers, robotics and drone hobbyists working with motor RPM, and students learning the relationship between frequency, angular velocity, and rotational speed.

Enter a frequency value and select its unit. Formula: Hertz = Value × Unit Factor, then each target unit = Hertz ÷ Target Factor.

Frequency Value

Frequency Type —
RPM & Angular Units

Waveform Comparison

Your entered frequency's waveform plotted against a 60 Hz reference wave over the same time window. Higher frequencies show more compressed cycles; lower frequencies show fewer, wider cycles. Illustrative scale — not a literal oscilloscope trace.

Your Entered Frequency 60 Hz Reference

SI Frequency Units

Hertz

—

Millihertz

—

mHz

Microhertz

—

µHz

Nanohertz

—

nHz

Kilohertz

—

kHz

Megahertz

—

MHz

Gigahertz

—

GHz

Terahertz

—

THz

Petahertz

—

PHz

Exahertz

—

EHz

Zettahertz

—

ZHz

Yottahertz

—

YHz

Ronnahertz

—

RHz

Quettahertz

—

QHz

Angular & Rotational Units

Radians/Sec

—

rad/s

Rev/Minute

—

rpm

Rev/Second

—

rps

Rev/Hour

—

rph

Rev/Day

—

rpd

Rev/Week

—

rpwk

Rev/Month

—

rpmo

Rev/Year

—

rpy

Formula: —

Conversions are mathematically exact for SI-prefixed and rotational units. The waveform chart is illustrative only.

How to Use the Frequency & RPM Converter

Enter Your Frequency Value

Type the frequency value from a meter reading, datasheet, motor nameplate, or spec sheet into the input field.

Select the Source Unit

Choose the unit your value is currently in — SI Frequency Units (Hertz through Quettahertz) or Angular & Rotational Units (rad/s, RPM, and more) are both supported.

Click Calculate

The converter instantly computes the equivalent value in all 22 supported frequency units at once, grouped for quick scanning — no need to convert one pair at a time.

Review Results and Print

Check the results across all unit cards, the exact formula used, and the waveform comparison chart. Use Print to capture results as they appear on screen for documentation.

Guide to Frequency Units Comprehensive Guide

A deeper look at where each frequency unit on this page comes from — the SI-prefixed units used in everyday electrical and RF work, and the angular/rotational units used in motors, drives, and mechanical systems.

SI-Prefixed Units (Nanohertz through Quettahertz)

Hertz, Millihertz, Microhertz, Nanohertz, Kilohertz, Megahertz, Gigahertz, Terahertz, Petahertz, Exahertz, Zettahertz, Yottahertz, Ronnahertz, and Quettahertz are all the same underlying unit — the hertz, one cycle per second — scaled by a power of ten. This is the International System of Units (SI) convention. Because every SI conversion is an exact power of ten, there is no rounding error going between any two of these units. Ronnahertz and Quettahertz are the newest SI prefixes, formally adopted in 2022.

Radians per Second (rad/s)

Angular frequency measures how fast an angle changes, in radians per second, rather than how many full cycles occur per second. Since one full cycle covers 2π radians, angular frequency (ω) equals 2π times the frequency in Hz. This unit is common in AC circuit analysis, control systems, and rotational mechanics.

Rotational Frequency Units (rpm, rps, rph, rpd, rpwk, rpmo, rpy)

These units express frequency as revolutions over a given time period rather than cycles per second. Revolutions per minute (rpm) is the most common — used for motor speed, drone propellers, and fans. Revolutions per second (rps) is numerically identical to Hz. The longer-period units (rph, rpd, rpwk, rpmo, rpy) are used for very slow rotational systems and use calendar-based time constants — an hour, day, week, average month, and Julian year, respectively.

This guide is provided for educational and reference purposes. Always confirm measured frequency values against a properly calibrated instrument before relying on them for any electrical or mechanical work.

Worked Examples

Three real-world conversion scenarios, worked step by step. Click "Load This Example" to run it in the calculator above.

1. AC Power Circuit — Hz to Radians/Second

US AC power runs at 60 Hz. An AC circuit calculation needs the angular frequency in radians per second. Convert 60 Hz to rad/s.

ω = 2π × 60 Hz ≈ 376.9911 rad/s

2. Wi-Fi Router — GHz to Hz

A Wi-Fi router datasheet lists a 5 GHz band. A firmware config field requires the value in Hz. Convert 5 GHz to Hz.

5 GHz × 1,000,000,000 = 5,000,000,000 Hz

3. Drone Motor — Hz to RPM

A drone motor's electrical frequency reads 400 Hz. The motor spec sheet lists speed in RPM. Convert 400 Hz to RPM.

400 Hz × 60 = 24,000 RPM

Quick Reference Table

Common real-world frequency values, for quick lookup without re-entering numbers.

Value	In Hz	Common Use
50 Hz	50	EU / UK AC mains power
60 Hz	60	US / Canada AC mains power
100 MHz	100,000,000	Typical FM radio station
433 MHz	433,000,000	ISM band — remotes, garage door openers
900 MHz	900,000,000	Cellular / ISM band
1.575 GHz	1,575,000,000	GPS L1 signal
2.4 GHz	2,400,000,000	Wi-Fi / Bluetooth band
2.45 GHz	2,450,000,000	Consumer microwave ovens
5 GHz	5,000,000,000	Wi-Fi band
3,600 RPM	60	2-pole induction motor synchronous speed at 60 Hz
10,000 RPM	166.67	Small high-speed motor / drone motor range

Frequently Asked Questions

How many kHz are in 1 Hz?

1 Hz equals 0.001 kHz. Divide a hertz value by 1,000 to get kilohertz, or multiply a kilohertz value by 1,000 to get hertz.

What's the difference between rad/s and Hz?

Hertz measures cycles per second, while radians per second (rad/s) measures angular velocity — the rate of angle change in radians. Since one full cycle equals 2π radians, angular frequency in rad/s equals 2π times the frequency in Hz. For example, 60 Hz equals about 376.99 rad/s. See the Guide to Frequency Units above for more detail.

How do I convert Hz to RPM?

Multiply the frequency in Hz by 60 to get revolutions per minute (RPM): 1 Hz equals 60 RPM. This conversion is commonly used for motor speed, drone propeller speed, and other rotational machinery specified in RPM rather than Hz.

What are petahertz, exahertz, and the other extreme-scale frequency units used for?

These units extend the SI frequency ladder beyond gigahertz and terahertz. Petahertz and exahertz appear in physics contexts like visible light and X-ray frequencies. Zettahertz, yottahertz, ronnahertz, and quettahertz are the newest SI prefixes, adopted in 2022, and are rarely encountered outside theoretical physics and future-proofed scientific notation.

Why does the waveform chart look different for high vs. low frequencies?

The chart compares your entered frequency's waveform against a 60 Hz reference wave over the same time window. A higher-frequency wave completes more full cycles in that window, so it appears compressed with more peaks, while a lower-frequency wave appears stretched out with fewer peaks — a visual demonstration of what a frequency value represents: cycles per second.