ElectroCalc

Frequency & Period Converter

Convert between frequency and period instantly. Hz, kHz, MHz, GHz, RPM, and rad/s.

Enter Frequency

Results

Enter valid component values.

T (period)+A−A

Common Frequencies Reference

FrequencyPeriodDescription
50 Hz20.0 msMains (Europe, Asia)
60 Hz16.7 msMains (Americas)
440 Hz2.27 msConcert pitch (A4)
1 kHz1.00 msAudio test tone
32.768 kHz0.0305 msRTC crystal
1 MHz1.00 µsCommon MCU clock
2.4 GHz0.417 nsWiFi / Bluetooth
5.8 GHz0.172 nsWiFi 5 GHz band

Frequency and Period

Frequency and period are two ways of describing the same thing: how fast something repeats. Frequency (f) counts cycles per second in hertz (Hz). Period (T) measures the time for one complete cycle. The relationship is simple: f = 1/T and T = 1/f.

In electronics, you encounter frequencies from sub-hertz (heartbeat sensors) to gigahertz (WiFi, Bluetooth). The 32.768 kHz crystal in every digital watch was chosen because 32768 = 2^15, which a chain of 15 flip-flops divides down to exactly 1 Hz for the seconds counter.

Angular frequency ω = 2πf (in rad/s) appears in formulas for impedance (XL = ωL, XC = 1/ωC) and transfer functions. RPM (revolutions per minute) is common in motors — divide by 60 to get Hz. These are all different units for the same physical quantity.

Conversion Formula

f = 1/T   T = 1/f

Key Points

  • f = 1/T — frequency and period are reciprocals
  • ω = 2πf — angular frequency in radians per second
  • RPM = f × 60 — used for rotating machinery
  • 32.768 kHz = 2^15 Hz — standard RTC crystal frequency

Applications

  • Oscillator and crystal selection
  • Timer/counter configuration for microcontrollers
  • Motor speed measurement and control
  • Audio and RF frequency analysis