Coulomb’s Law Calculator
Find the electrostatic force between two point charges.
The force between charges
Coulomb’s law describes the electrostatic force between two charges, and it mirrors gravity in form: strength drops with the square of distance. It is the starting point for electrostatics.
Two microcoulomb-scale charges half a metre apart repel with a force on the order of hundredths of a newton. Opposite signs mean attraction; the calculator reports both magnitude and direction.
Precise and private
It applies Coulomb’s law in your browser, so nothing you enter is uploaded.
Frequently Asked Questions
What is Coulomb’s law?
The force between two point charges is proportional to the product of the charges and inversely proportional to the square of the distance between them.
What is the constant k?
Coulomb’s constant, about 8.988 × 10⁹ newton-metres squared per coulomb squared, in a vacuum.
Is the force attractive or repulsive?
Like charges repel and opposite charges attract. The tool reports the magnitude and the direction.
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