Current Calculator
Calculate electric current using Ohm's law (I = V / R) or the power formula (I = P / V). Enter voltage and resistance to find current.
Enter voltage and resistance to calculate current.
Current Formula (Ohm's Law)
I = V / R
Electric current (I) is the rate of flow of electric charge. It equals voltage (V) divided by resistance (R).
Alternative Current Formulas
I = P / V (from power and voltage)
I = √(P / R) (from power and resistance)
I = √(P / R) (from power and resistance)
Example: A 12 V battery connected to a 4 Ω resistor.
I = 12 / 4 = 3 A
I = 12 / 4 = 3 A
FAQ
What is the difference between AC and DC current?
DC (Direct Current) flows in one direction constantly. AC (Alternating Current) periodically reverses direction. Household electricity is AC; batteries provide DC.
What is a milliamp?
A milliamp (mA) is 1/1000 of an ampere. Small electronics often draw current in milliamps.
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Last updated: 2026-08-08