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 microsecond?

A microsecond is a unit of time equal to one millionth of a second. It is used in electronics, radar systems, telecommunications, and measuring the speed of high-frequency processes.

Real-world uses

Microseconds are used to measure CPU instruction execution times, radar pulse durations, and ultrasonic echo intervals. High-frequency trading systems operate on microsecond timescales, and camera flash durations are typically 1–1,000 µs.

History

The microsecond became measurable with the development of oscilloscopes and electronic timing circuits in the early 20th century. The prefix "micro-" was adopted from Greek and formally standardized as an SI prefix in 1960.

Common mistakes

Using "us" instead of "µs" as the symbol, which can cause confusion with the word "us" in text. Also, conflating microseconds with milliseconds in performance benchmarks, leading to 1000x reporting errors.

When is this conversion used?

Converting second to microsecond 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 = 1,000,000 microsecond

1 microsecond = 0.000001 second

How to convert second to microsecond

To convert second to microsecond, multiply the value by 1,000,000.

To convert microsecond back to second, multiply by 0.000001.

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 microsecond

secondmicrosecond
0.1100,000
0.5500,000
11,000,000
22,000,000
55,000,000
1010,000,000
2525,000,000
5050,000,000
100100,000,000
250250,000,000
500500,000,000
1,0001.000000e+09

Common values

secondmicrosecond
Blink of an eye0.3 second300,000 microsecond
Average pop song210 second210,000,000 microsecond
Feature film7,200 second7.200000e+09 microsecond
One work day (8 hrs)28,800 second2.880000e+10 microsecond
One calendar year31,536,000 second3.153600e+13 microsecond