Picometers (pm)

The picometer is a metric unit of length equal to one trillionth of a meter, or one thousandth of a nanometer.

Convert picometers to any length unit

1 picometer = 3.9370079 × 10-11 inches

Quick facts

Unit
Picometer (plural: picometers)
Symbol
pm
Measures
Length / Distance
System
Metric (SI)
Equals
1 × 10-12 meters
Definition
One trillionth of a meter (10⁻¹² m).
Also written
picometre

1 picometer in other units

Inches3.9370079 × 10-11 in
Meters1 × 10-12 m
Centimeters1 × 10-10 cm
Feet3.2808399 × 10-12 ft
Kilometers1 × 10-15 km
Miles6.2137119 × 10-16 mi
Millimeters1 × 10-9 mm
Yards1.0936133 × 10-12 yd

What is a picometer?

The picometer is a metric unit of length equal to one trillionth of a meter, or one thousandth of a nanometer. It is used for atomic radii and bond lengths: a carbon atom has a radius of about 70 pm, and the bond between two hydrogen atoms is about 74 pm long.

Where the picometer sits among length units

The picometer is number 5 of 231 on our scale of length units, ordered from smallest to largest.

Planck length1 pm = 6.187142 × 1022 ℓP Femtometer1 pm = 1,000 fm Classical electron radius1 pm = 354.869 rₑ X unit1 pm = 9.97904 xu Picometerthis unit ångström1 Å = 100 pm Nanometer1 nm = 1,000 pm Micrometer1 µm = 1,000,000 pm Thou1 th = 25,400,000 pm

What picometers are used for

  • Atomic and ionic radii
  • Chemical bond lengths
  • X-ray and gamma-ray wavelengths

Picometers in real life

One picometer is about 588 protons laid end to end.

Top picometer conversions

Common amounts of picometers

Convert picometers to all 230 other units

Metric (SI)

Imperial & US customary

US survey

Nautical

Astronomical

Scientific & atomic

Ancient

East & Southeast Asian

South Asian & Middle Eastern

European (pre-metric)

Spanish & Portuguese

Everyday comparisons

Convert to picometers

Frequently asked questions

What is a picometer?

The picometer is a metric unit of length equal to one trillionth of a meter, or one thousandth of a nanometer.

How is the picometer defined?

One trillionth of a meter (10⁻¹² m).

How many inches are in a picometer?

One picometer equals 3.9370079e-11 inches.

How many meters are in a picometer?

One picometer equals 1e-12 meters.

How many centimeters are in a picometer?

One picometer equals 1e-10 centimeters.