Length · Unit Converter

Convert Micrometer to Petameter

Convert micrometers to petameters instantly. 1 micrometer = 1e-21 petameter — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Petameter to Micrometer converter for the reverse conversion.

Written by Sunith Babu L, Ph.D., Lead Engineer Reviewed by Girish V Kulkarni Ph.D.
Length category 2 min read Published Last reviewed Updated

Units explained

Metric / SI

Micrometer

What is a micrometer?

A micrometer (also called a micron) is a metric unit of length equal to one millionth of a meter (1×10⁻⁶ m). It is the standard unit for measuring microscopic dimensions in biology, materials science, and semiconductor manufacturing.

Origin of the micrometer

Defined alongside the meter when France adopted the metric system in 1795, using the SI prefix micro- (from Greek mikros, "small") to denote one-millionth.

Where it is used

Micrometers are used to measure cell sizes, bacteria, semiconductor process nodes, fiber diameters, dust particles, and wavelengths of infrared radiation. The diameter of a human hair is about 70 μm.

When and where it was developed

Defined in 1795 as part of the original French metric system; the name "micron" was officially deprecated by the BIPM in 1967 in favor of micrometer.

Metric / SI

Petameter

What is a petameter?

A petameter is a metric unit of length equal to one quadrillion meters (1×10¹⁵ m). It is rarely used in everyday or scientific contexts; astronomers prefer the light-year or parsec for these scales.

Origin of the petameter

The petameter uses the SI prefix peta- (from Greek penta, five, by analogy with the exponent's relation to thousand-cubed-cubed), adopted by the CGPM in 1975 to denote 10¹⁵.

Where it is used

Petameters could express interstellar-scale distances but are almost never used in practice. A light-year is approximately 9.46 Pm; astronomy uses light-years and parsecs as standard.

When and where it was developed

SI prefix peta- adopted in 1975; the petameter is rarely used because astronomy has well-established non-SI units (light-year, parsec) for this scale.

Micrometer to Petameter conversion formula

The relationship between micrometers and petameters:

1 μm = 1e-21 Pm
1 Pm = 1e+21 μm

To convert micrometers to petameters, multiply the value in micrometers by 1e-21. To reverse, multiply petameters by 1e+21.

How to use this converter

Type a value into the calculator. The result in petameters updates as you type. Tap a quick value, copy the result with one click, or use the swap arrow to jump straight to the Petameter to Micrometer converter for the reverse direction.

Step-by-step: convert micrometers to petameters

  1. Write down the value in micrometers (μm).
  2. Multiply that value by the factor 1e-21.
  3. The product is the equivalent value in petameters (Pm).
  4. To reverse, multiply the petameter value by 1e+21.

Worked examples

Example 1 — Convert 1 μm to Pm:
1 × 1e-21 = 1e-21 Pm

Example 2 — Convert 100 μm to Pm:
100 × 1e-21 = 1e-19 Pm

Real-world example — Paper and film thicknesses

At the thickness of office paper (roughly 3 micrometers), converting between sub-millimeter units is routine for packaging and printing buyers comparing quotes from metric and US suppliers.

3 μm × 1e-21 = 3e-21 Pm

Real-world example — Plastic-film thickness alternates

A 150-micrometer plastic film converts cleanly to petameters — useful for packaging buyers reconciling supplier datasheets across metric and US measurement systems.

150 μm × 1e-21 = 1.5e-19 Pm

Real-world example — Hair-width scale measurements

A 70-micrometer measurement (about the diameter of a human hair) is the kind of value materials engineers regularly express in adjacent micro-scale units like petameters for direct comparison across supplier datasheets.

70 μm × 1e-21 = 7e-20 Pm

Micrometer to Petameter conversion table

Standard reference values for converting micrometers to petameters:

Micrometer [μm]Petameter [Pm]
0.011e-23
0.11e-22
11e-21
22e-21
33e-21
44e-21
55e-21
101e-20
202e-20
303e-20
404e-20
505e-20
1001e-19
5005e-19
10001e-18

Frequently asked questions

How many petameters is 1 micrometer?
1 micrometer equals 1e-21 petameter.
How do I convert micrometers to petameters?
Multiply the value in micrometers by 1e-21 to get petameters.
How do I convert petameters back to micrometers?
Multiply the value in petameters by 1e+21, or use the Petameter to Micrometer converter.
How many petameters is 100 micrometers?
100 micrometers equals 1e-19 petameters, because 100 × 1e-21 = 1e-19.

Convert Micrometer to other length units

Show all Micrometer conversions

Sources & references

Conversion factor (1 μm = 1e-21 Pm) verified against the following authoritative sources:

Results are provided for general reference. Verify critical measurements against an authoritative standard.