Electric Field Calculator
Calculate the electric field from a charge or from force on a test charge.
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Choose your calculation mode: from a point charge and distance, or from force on a test charge. Enter the values and the calculator computes the electric field strength instantly.
About Electric Field
The electric field describes the force per unit charge at any point in space. For a point charge Q, the field at distance r equals kQ/r2, where k is Coulomb's constant. Alternatively, the field can be determined by measuring the force on a known test charge: E = F/q. Electric fields are fundamental to understanding capacitors, electromagnetic waves, and the behavior of charged particles in physics and engineering.
Frequently Asked Questions
What is an electric field?
An electric field is a region around a charged object where other charges experience a force. It is measured in newtons per coulomb (N/C) or equivalently volts per meter (V/m).
How does the electric field vary with distance?
For a point charge, the electric field decreases with the square of the distance. Doubling the distance reduces the field strength to one quarter.
What is the direction of the electric field?
The electric field points away from positive charges and toward negative charges. It indicates the direction a positive test charge would be pushed.