Fundamental Physical Constants

Fundamental physical constants data from NIST CODATA, provided as an ES Module.

Installation

npm install fundamental-physical-constants

Usage

Node.js / Bundler

import { constants } from 'fundamental-physical-constants';

// Access any constant by its name
console.log(constants['Avogadro constant']);
// {
//   value: '6.02214076e23',
//   uncertainty: '(exact)',
//   unit: 'mol^-1'
// }

console.log(constants['Planck constant'].value);
// '6.62607015e-34'

console.log(constants['speed of light in vacuum']);
// {
//   value: '299792458',
//   uncertainty: '(exact)',
//   unit: 'm s^-1'
// }

Browser with Import Map

You can also use this package directly in the browser via esm.sh or unpkg with an import map:

<script type="importmap">
{
  "imports": {
    "fundamental-physical-constants": "https://esm.sh/fundamental-physical-constants"
  }
}
</script>

<script type="module">
  import { constants } from 'fundamental-physical-constants';
  console.log(constants['Avogadro constant']);
</script>

Or using unpkg:

<script type="importmap">
{
  "imports": {
    "fundamental-physical-constants": "https://unpkg.com/fundamental-physical-constants/FundamentalPhysicalConstants.js"
  }
}
</script>

Data Structure

Each constant is an object with the following properties:

| Property | Description | |----------|-------------| | value | The numerical value of the constant | | uncertainty | The measurement uncertainty, or (exact) for defined constants | | unit | The unit of measurement |

Available Constants

The package includes over 300 physical constants, including but not limited to:

• Avogadro constant
• Boltzmann constant
• Planck constant
• speed of light in vacuum
• elementary charge
• electron mass
• proton mass
• neutron mass
• Bohr radius
• fine-structure constant
• gravitational constant
• Stefan-Boltzmann constant
• Rydberg constant
• ...and many more

To see the full list of available constants:

import { constants } from 'fundamental-physical-constants';

console.log(Object.keys(constants));

Data Source

The constants data is sourced from the NIST Reference on Constants, Units, and Uncertainty (CODATA).

License

MIT