1 femtosecond
1 fsTime · definition
Time conversions use a Julian year of exactly 365.25 days.
Time
Just how long is 1 femtosecond?
One femtosecond is one quadrillionth of a second (10⁻¹⁵ s).
Fleeting instants
1 fs
ELAPSED TIME
1 femtosecond
Time conversions use a Julian year of exactly 365.25 days.
1 fsTime
0
Atomic-scale transition
An atomic-scale transition is a rapid change in the energy state of an atom, often occurring in extremely short intervals.
1 fsTime
0
Both timelines start together. Length measures elapsed time, not a physical distance.
A little perspective
1 femtosecond is approximately equal to the duration of an atomic-scale transition.
Measurements, assumptions & sources +
1 femtosecond
Time: 1 fs; definition.
Time conversions use a Julian year of exactly 365.25 days.
Atomic-scale transition
Time: 1 fs; reference interval.
A chosen femtosecond process interval; real transitions span many timescales.
Defined examples — our methodology
The marked time is calibrated. Unmeasured illustration details are representative.
Measurement details
Why these numbers?
Compare 1 femtosecond with the duration of an atomic-scale transition. The notes below explain how each value was chosen.
Atomic-scale transition
1 fsTime · reference interval
A chosen femtosecond process interval; real transitions span many timescales.
- Comparing
- Time ↔ Time
- Relative size
- 1 femtosecond is approximately equal to the duration of an atomic-scale transition.
How to read the visual
The diagram uses the recorded measurements. Details outside the marked spans do not set the scale.
- The duration of an atomic-scale transition: The measurement is labelled reference interval. Check the source notes for its basis.
A duration is an interval, not a calendar date.
1 × 10⁻¹⁵ sseconds
2.7778 × 10⁻¹⁹ hhours
1.1574 × 10⁻²⁰ daysdays
3.1688 × 10⁻²³ yearsyears
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