Picoseconds to Hours (ps to h)

1 picosecond equals 2.777777778×10⁻¹⁶ hours (rounded).

1 picosecond = 2.777777778×10⁻¹⁶ hours

How to convert picoseconds to hours

To convert picoseconds to hours, multiply the number of picoseconds by 2.777777778×10⁻¹⁶. The factor is rounded to 10 significant digits. To go the other way, multiply hours by 3.6×10¹⁵.

hours = picoseconds × 2.777777778×10⁻¹⁶

Example: 10 picoseconds = 2.777777778×10⁻¹⁵ hours.

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

Picosecond (ps)

ScientificCurrent unit

One trillionth of a second. Used for very fast electronics.

Pico comes from SI prefix naming and stands for 10 to the power of minus 12, so a picosecond is one trillionth of a second. The BIPM and NIST prefix tables both list it with the symbol p, and the unit is written ps. It is an exact decimal fraction with no historical variation, which is why the factor used here carries no uncertainty.

Picoseconds matter where signals and molecules move too fast for milliseconds or nanoseconds to be useful. Light in a vacuum travels about 0.30 mm in one picosecond, so a millimetre takes roughly 3.3 ps. A 1 THz electromagnetic wave has a cycle time of 1.0 ps, the unit interval of a 10 Gbit/s serial link is 100 ps, and a 3.0 GHz processor cycle lasts about 330 ps. Streak cameras can resolve events on single-digit picosecond timescales, and Wikipedia lists the lifetime of a hydronium ion in water as about 1 ps. A picosecond is one thousandth of a nanosecond.

1 picosecond = 1×10⁻¹² seconds (exactly).

Sources: Wikipedia: Picosecond; BIPM: SI prefixes; NIST: Metric (SI) prefixes

Hour (h)

Metric (SI)Current unit

60 minutes or 3,600 seconds, one twenty-fourth of a mean solar day.

Egyptian astronomers gave us the twelve. Coffin lids from about 2150 BC show the night divided into exactly 12 intervals, tied to the rising of star groups called decans, and the day was later split into 12 hours with sundials. These were seasonal hours, a twelfth of the daylight, so a summer hour was longer than a winter one. The word itself comes from Greek hora, originally any span of time, through Latin and Old French into English in the 13th century.

Equal hours of 1/24 of a day were probably first proposed by Hipparchus, and mechanical clocks made them the practical choice, since a clock showing seasonal hours had to be readjusted every morning and evening. Today the hour is exactly 3,600 seconds and is a non-SI unit accepted for use with the SI. Civil time still bends it a little: UTC hours have lasted 3,601 seconds 27 times since 1972 to keep clocks within 0.9 seconds of the Earth's rotation. In practice we use it for working shifts, travel times and electricity bills measured in kilowatt-hours.

1 hour = 3,600 seconds (exactly).

Sources: Wikipedia: Hour; BIPM: SI Brochure, 9th edition

Related conversions

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