Length · Unit Converter

Convert Bohr Radius to Meter

Convert bohr radii to meters instantly. 1 bohr radius = 5.291772e-11 meter — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Meter to Bohr Radius 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

Atomic / Physics

Bohr Radius

What is a bohr radius?

The Bohr radius is approximately 5.292×10⁻¹¹ meters — the most probable distance between the proton and electron in a hydrogen atom in its ground state.

Origin of the bohr radius

Defined by Niels Bohr in his 1913 model of the hydrogen atom. The current CODATA 2018 value of 5.29177210903×10⁻¹¹ m is derived from the elementary charge, electron mass, and Planck's constant.

Where it is used

The Bohr radius is used throughout atomic physics, quantum chemistry, and computational chemistry as the natural length scale for electronic-structure calculations. The atomic unit (a.u.) of length equals the Bohr radius.

When and where it was developed

Defined by Bohr in 1913; current value via CODATA 2018.

Metric / SI

Meter

What is a meter?

The meter is the SI base unit of length. Since 2019, the meter has been defined by fixing the numerical value of the speed of light in vacuum to exactly 299,792,458 meters per second. Every other SI length unit derives from the meter.

Origin of the meter

The meter was originally defined in 1793 by the French Academy of Sciences as one ten-millionth of the distance from the equator to the North Pole along a meridian through Paris. It has been redefined multiple times — by physical prototype, then by atomic transitions, and finally in 2019 by fundamental physical constants.

Where it is used

The meter is the international standard for length in science, engineering, construction, athletics, and everyday measurement in metric countries. It underpins definitions of area (m²), volume (m³), and most derived SI units.

When and where it was developed

Established 1793 in France; ratified internationally via the Metre Convention 1875; redefined in 1960, 1983, and most recently 2019 when the SI redefinition fixed it to the speed of light.

Bohr Radius to Meter conversion formula

The relationship between bohr radii and meters:

1 a₀ = 5.291772e-11 m
1 m = 1.889726e+10 a₀

To convert bohr radii to meters, multiply the value in bohr radii by 5.291772e-11. To reverse, multiply meters by 1.889726e+10.

How to use this converter

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

Step-by-step: convert bohr radii to meters

  1. Write down the value in bohr radii (a₀).
  2. Multiply that value by the factor 5.291772e-11.
  3. The product is the equivalent value in meters (m).
  4. To reverse, multiply the meter value by 1.889726e+10.

Worked examples

Example 1 — Convert 1 a₀ to m:
1 × 5.291772e-11 = 5.291772e-11 m

Example 2 — Convert 100 a₀ to m:
100 × 5.291772e-11 = 5.291772e-9 m

Real-world example — Bridging nine orders of magnitude

500 million bohr radii equals a value comfortably in the human-scale meters range. Physics problems that span this gap are common when comparing the wavelength of light to the path length of an experiment.

5e+8 a₀ × 5.291772e-11 = 0.0264588605 m

Real-world example — From sub-micron to human scale

One billion bohr radii equals one meter — the conversion that drives home the gulf between atomic-scale features and everyday objects in physics curricula.

1e+9 a₀ × 5.291772e-11 = 0.0529177211 m

Bohr Radius to Meter conversion table

Standard reference values for converting bohr radii to meters:

Bohr Radius [a₀]Meter [m]
0.015.291772e-13
0.15.291772e-12
15.291772e-11
21.058354e-10
31.587532e-10
42.116709e-10
52.645886e-10
105.291772e-10
201.058354e-9
301.587532e-9
402.116709e-9
502.645886e-9
1005.291772e-9
5002.645886e-8
10005.291772e-8

Frequently asked questions

How many meters is 1 bohr radius?
1 bohr radius equals 5.291772e-11 meter.
How do I convert bohr radii to meters?
Multiply the value in bohr radii by 5.291772e-11 to get meters.
How do I convert meters back to bohr radii?
Multiply the value in meters by 1.889726e+10, or use the Meter to Bohr Radius converter.
How many meters is 100 bohr radii?
100 bohr radii equals 5.291772e-9 meters, because 100 × 5.291772e-11 = 5.291772e-9.

Convert Bohr Radius to other length units

Show all Bohr Radius conversions

Sources & references

Conversion factor (1 a₀ = 5.291772e-11 m) verified against the following authoritative sources:

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