Length · Unit Converter

Convert Microbarn to Millibarn

Convert microbarns to millibarns instantly. 1 microbarn = 0.001 millibarn — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Millibarn to Microbarn 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

Scientific / Physics

Microbarn

What is a microbarn?

A microbarn is a scientific unit of area equal to exactly 10⁻³⁴ m² (10⁻⁶ barn).

Origin of the microbarn

Derived from the barn using the standard SI micro- prefix. Identical in value to the humor unit 'outhouse'.

Where it is used

Microbarns appear in particle physics for moderately rare process cross-sections. They are widely used in heavy-ion physics and electroweak cross-section measurements.

When and where it was developed

Standard derivative of the barn unit.

Scientific / Physics

Millibarn

What is a millibarn?

A millibarn is a scientific unit of area equal to exactly 10⁻³¹ m² (1/1000 of a barn).

Origin of the millibarn

Derived from the barn using the standard SI milli- prefix.

Where it is used

Millibarns are widely used in particle physics for medium-strength interaction cross-sections. The total proton-proton inelastic cross-section is on the order of 70 mb at LHC energies.

When and where it was developed

Standard derivative of the barn unit.

Microbarn to Millibarn conversion formula

The relationship between microbarns and millibarns:

1 µb = 0.001 mb
1 mb = 1000 µb

To convert microbarns to millibarns, multiply the value in microbarns by 0.001. To reverse, multiply millibarns by 1000.

How to use this converter

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

Step-by-step: convert microbarns to millibarns

  1. Write down the value in microbarns (µb).
  2. Multiply that value by the factor 0.001.
  3. The product is the equivalent value in millibarns (mb).
  4. To reverse, multiply the millibarn value by 1000.

Worked examples

Example 1 — Convert 1 µb to mb:
1 × 0.001 = 0.001 mb

Example 2 — Convert 100 µb to mb:
100 × 0.001 = 0.1 mb

Real-world example — Molecular dimensions

The diameter of small molecular structures (around 2 microbarns) is often converted into related sub-micron units when comparing measurements across different microscopy techniques or imaging modalities.

2 µb × 0.001 = 0.002 mb

Real-world example — Wavelengths across the spectrum

Optical and atomic-scale phenomena are routinely cross-converted between sub-micron units. A photon of wavelength 800 microbarns can be re-expressed in millibarns for direct comparison with another instrument's calibration data sheet.

800 µb × 0.001 = 0.8 mb

Microbarn to Millibarn conversion table

Standard reference values for converting microbarns to millibarns:

Microbarn [µb]Millibarn [mb]
0.011e-5
0.11e-4
10.001
20.002
30.003
40.004
50.005
100.01
200.02
300.03
400.04
500.05
1000.1
5000.5
10001

Frequently asked questions

How many millibarns is 1 microbarn?
1 microbarn equals 0.001 millibarn.
How do I convert microbarns to millibarns?
Multiply the value in microbarns by 0.001 to get millibarns.
How do I convert millibarns back to microbarns?
Multiply the value in millibarns by 1000, or use the Millibarn to Microbarn converter.
How many millibarns is 100 microbarns?
100 microbarns equals 0.1 millibarns, because 100 × 0.001 = 0.1.

Convert Microbarn to other area units

Show all Microbarn conversions

Sources & references

Conversion factor (1 µb = 0.001 mb) verified against the following authoritative sources:

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