What is second?
The second is the SI base unit of time. It is used globally in science, engineering, computing, and everyday life, and is the foundation upon which all other time units are built.
Real-world uses
The second is the SI base unit of time, fundamental to all scientific measurement, computing clock cycles, athletic timing, and GPS satellite synchronization. Everyday timekeeping, cooking timers, and traffic light cycles all rely on seconds.
History
The concept of dividing the day into 86,400 parts dates to ancient Babylonian and Egyptian timekeeping. Since 1967, the SI second has been defined as 9,192,631,770 periods of the radiation from a caesium-133 atom.
Common mistakes
Assuming a second has always been 1/86,400 of a day. The modern SI second is defined by caesium atom vibrations and is independent of Earth's rotation, which varies slightly due to tidal friction.
What is nanosecond?
A nanosecond is a unit of time equal to one billionth of a second. It is critical in computer processor timing, high-frequency trading, optical communications, and physics experiments.
Real-world uses
Nanoseconds are used in computing to measure memory access times (DRAM latency is typically 10–100 ns), CPU cache operations, and network packet timestamps. Light travels approximately 30 cm in one nanosecond, a fact used in signal timing.
History
The nanosecond became a practical unit with the advent of digital electronics in the 1960s. Grace Hopper famously used a 30 cm piece of wire to demonstrate the distance light travels in a nanosecond, making the concept tangible for non-engineers.
Common mistakes
Underestimating how short a nanosecond is—light only travels about one foot in a nanosecond. Also, confusing nanoseconds with microseconds in performance specifications, which differ by a factor of 1,000.
When is this conversion used?
Converting second to nanosecond is useful in the time domain when comparing values across different measurement standards or applying formulas that require a specific unit.
Worked examples
1 second = 999,999,999.99999988 nanosecond
1 nanosecond = 1.000000e-09 second
How to convert second to nanosecond
To convert second to nanosecond, multiply the value by 999,999,999.99999988.
To convert nanosecond back to second, multiply by 1.000000e-09.
Measurement standards
The SI second is defined as the duration of 9,192,631,770 periods of the radiation corresponding to the transition between two hyperfine levels of the ground state of the caesium-133 atom, maintained by the BIPM and national metrology institutes worldwide.
Did you know?
Earth's rotation is gradually slowing due to tidal friction with the Moon. To keep atomic time aligned with solar time, "leap seconds" have been inserted 27 times since 1972 — though they are scheduled to be abolished by 2035.
Quick reference: second to nanosecond
| second | nanosecond |
|---|---|
| 0.1 | 100,000,000 |
| 0.5 | 499,999,999.99999994 |
| 1 | 999,999,999.99999988 |
| 2 | 2.000000e+09 |
| 5 | 5.000000e+09 |
| 10 | 1.000000e+10 |
| 25 | 2.500000e+10 |
| 50 | 5.000000e+10 |
| 100 | 1.000000e+11 |
| 250 | 2.500000e+11 |
| 500 | 5.000000e+11 |
| 1,000 | 1.000000e+12 |
Common values
| second | nanosecond | |
|---|---|---|
| Blink of an eye | 0.3 second | 300,000,000 nanosecond |
| Average pop song | 210 second | 2.100000e+11 nanosecond |
| Feature film | 7,200 second | 7.200000e+12 nanosecond |
| One work day (8 hrs) | 28,800 second | 2.880000e+13 nanosecond |
| One calendar year | 31,536,000 second | 3.153600e+16 nanosecond |
Available Time units
More second conversions
- Convert second to minute
- Convert second to hour
- Convert second to day
- Convert second to week
- Convert second to year (365 d)
- Convert second to millisecond
- Convert second to microsecond
- Convert second to nanosecond
- Convert second to century (100 yr)
Assumption: year is defined as 365 days and century values are approximate.