Axis

Time & duration

zeptosecondzs

Zepto-scaled variant of the second, exactly zs = 0.000000000000000000001 base unit.

Dimension
time
Canonical signature
T
System
si
Exactness
Exact

Definition record

How this unit is defined

Canonical base
1 zs = 1e-21 s
Conversion type
linear
Historical notes
Defined from the caesium-133 hyperfine transition frequency (SI 2019).
Aliases
zepto sec, zepto seconds, zepto secs

Same dimension

Common conversions

Every conversion routes through the canonical base of the dimension.

1 zs = 1e-21 s

Exact relationship

10 zs = 1e-20 s

Exact relationship