Series Resistors Calculator
Calculate total resistance for series resistors.
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Enter up to five resistance values in ohms. Leave unused fields blank. The calculator shows the total series resistance, which is the sum of all entered values.
About Series Resistors
When resistors are connected in series, the same current flows through each one and their resistances add directly. The total resistance is always the sum of the individual values: Rt = R1 + R2 + ... This is the simplest circuit combination rule. Series resistance is used in voltage dividers, current limiters, and creating specific resistance values from standard components.
Frequently Asked Questions
How do resistors combine in series?
In series, resistances simply add: Rt = R1 + R2 + ... The total resistance is always greater than any individual resistor.
What is a series circuit?
In a series circuit, components are connected end-to-end so the same current flows through each one. The voltage divides among the resistors proportionally to their resistance.
Why would you connect resistors in series?
To increase total resistance, divide voltage, or create a specific resistance value not available as a single component. Series connections are also used in voltage dividers.