Electric Field Calculator

Calculate electric field strength (N/C) from a point charge, parallel plates, or two-charge superposition. Includes electric potential, force, and energy.

μC
m
Electric Field
Electric Potential
Force on 1 μC Test Charge
Extended More scenarios, charts & detailed breakdown
μC
m
Electric Field E
Electric Potential
Force on 1 μC
Professional Full parameters & maximum detail
μC
m
°
μC
μC
μC

Field Strength

Electric Field (E)
Electric Potential (V)

Components & Force

E field — X component
E field — Y component
Force on test charge
Potential Energy (U)

How to Use This Calculator

  1. Enter the source charge in microcoulombs (μC).
  2. Enter the distance from the charge in meters.
  3. Click Calculate to get electric field strength, electric potential, and force on a 1 μC test charge.
  4. Use Extended tabs for parallel plates or two-charge problems.

Formula

E = kQ ÷ r²  (Point Charge)

k = 8.99 × 10⁹ N·m²/C² (Coulomb's constant)

Electric Potential: V = kQ ÷ r

Force on test charge q: F = qE

Example

Example: Q = 2 μC, r = 0.3 m → E = (8.99×10⁹ × 2×10⁻⁶) ÷ 0.09 = 199,778 N/C

Frequently Asked Questions

  • An electric field is a region around a charged object where another charge experiences a force. Its strength E (N/C or V/m) equals the force per unit positive test charge: E = F ÷ q.
  • E = kQ ÷ r², where k = 8.99×10⁹ N·m²/C², Q is the source charge in coulombs, and r is the distance in meters.
  • E = V ÷ d, where V is the voltage across the plates and d is the separation in meters. The field is uniform between ideal parallel plates.
  • Electric potential V (volts) at distance r from charge Q is V = kQ ÷ r. It represents potential energy per unit charge. Unlike field, potential is a scalar.
  • The net electric field is the vector sum of fields from all individual charges. For charges on a line, fields pointing in opposite directions subtract; same direction fields add.

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