What this converter does
This converter turns a frequency in hertz into its period in seconds and back. The two are reciprocals: a higher frequency means a shorter period. Type a frequency and read the time for one cycle instantly, or swap to go the other way.
A 50 Hz mains supply has a 20-millisecond period; a 1 Hz signal takes a full second per cycle. Handy for timing, signals and control loops.
The units it covers
Frequency and period are reciprocals — one is simply one divided by the other, so they are inversely related, not linked by a fixed factor.
View all units & their values
| Unit | Symbol | Value | Mainly used |
|---|---|---|---|
| Frequency | Hz | f | Cycles per second |
| Period | s | T | Seconds for one cycle |
The formula
The period is one divided by the frequency, and the frequency is one divided by the period:
T = 1 ÷ fWhere:
- f = frequency in hertz
- T = period in seconds
Worked example
Find the period of a 50 Hz mains signal.
T = 1 ÷ f1 ÷ 50 = 0.02 s (20 ms)So 50 Hz has a period of 20 milliseconds per cycle.
The units in this example
Cycles per second. The higher it is, the shorter the time for one cycle.
- 1 Hz = 1 s
- 50 Hz = 20 ms
- 60 Hz ≈ 16.7 ms
- 1 kHz = 1 ms
The time for one complete cycle. Its reciprocal is the frequency.
- 1 s = 1 Hz
- 20 ms = 50 Hz
- 1 ms = 1 kHz
- T = 1 ÷ f