Years to Shakes (yr to shake)

1 year equals 3.1556952×10¹⁵ shakes exactly.

1 year = 3.1556952×10¹⁵ shakes

How to convert years to shakes

To convert years to shakes, multiply the number of years by 3.1556952×10¹⁵. This factor is exact. To go the other way, multiply shakes by 3.168873851×10⁻¹⁶ (rounded).

shakes = years × 3.1556952×10¹⁵

Example: 10 years = 3.1556952×10¹⁶ shakes.

Months and years are not constant. This site uses the average Gregorian year of 365.2425 days, so one 'year' converts to 365.2425 days, not 365; use 'common year' for exactly 365 days.

About these units

Year (yr)

CalendarCurrent unit

The average Gregorian calendar year of 365.2425 days (31,556,952 seconds). A common year has 365 days and a leap year 366.

A year is the Earth's trip around the Sun, but there are several versions. The tropical year, which tracks the seasons, is about 365.2422 days. The sidereal year, measured against the stars, is about 365.2564 days, roughly 20 minutes longer, because the Earth's axis precesses. Calendars must squeeze these into whole days, which is the origin of leap years. English year descends from Old English gear, while Latin annus, the source of annual, comes from a different root.

The Gregorian calendar, introduced by Pope Gregory XIII's bull of 24 February 1582, fixed the problem of Julian drift that had moved the March equinox away from 21 March and upset the date of Easter. Ten days were skipped, so Thursday 4 October was followed by Friday 15 October. Its rule of skipping leap days in century years not divisible by 400 gives a mean year of 365.2425 days, the value this site uses for the year. Britain and its empire switched in 1752 and Russia in 1918. Scientists write the year as a, with the Julian year fixed at 31,557,600 seconds.

1 year = 31,556,952 seconds (exactly).

Sources: Wikipedia: Year; Wikipedia: Gregorian calendar

Shake (shake)

ScientificTraditional unit (still used in some regions)

Exactly 10 nanoseconds. Coined at the Manhattan Project for nuclear chain reactions, from the phrase 'two shakes of a lamb's tail'.

Physicists on the wartime Manhattan Project needed a handy name for an interval that kept turning up in their chain-reaction calculations, and they settled on the shake. It is defined as 10 nanoseconds, or 10 to the power of minus 8 second. The name plays on the English idiom about something happening in two shakes of a lamb's tail, meaning very quickly.

One step of a fission chain, in which a neutron causes a fission that releases more neutrons, takes roughly one shake, and a whole reaction is typically over within 50 to 100 shakes, according to Wikipedia. The shake was coined in the same circle and for similar reasons as the barn, a unit of cross-sectional area. It is an informal metric unit rather than an SI unit. A shake equals 10,000 picoseconds, and 100 million shakes make one second.

1 shake = 1×10⁻⁸ seconds (exactly).

Sources: Wikipedia: Shake (unit); Wikipedia: Picosecond

Related conversions

See all time units.