Units of Time
4 units of time in the database, across 4 measurement systems, each with its exact or best-known SI value.
| Unit | Symbol | Quantity | Value in SI |
|---|---|---|---|
| Second | s | Time | Base unit; caesium-133 frequency = 9,192,631,770 Hz exactly |
| Hertz | Hz | Frequency | 1 Hz = 1 s⁻¹ |
| Day | d | Time | 1 d = 86,400 s (exact) |
| Julian year | a | Time | 365.25 d = 31,557,600 s (exact) |