Resistors In Series

Add up to 10 resistors and instantly get total resistance, current draw, and voltage drop across each resistor.

Resistor Values

Enter to calculate current and voltage drops.

Results

Total Resistance
Ω
Current
mA
Power (total)
mW
Add at least one resistor to see results.

Summary

Add up to 10 resistors and instantly get total resistance, current draw, and voltage drop across each resistor.

How it works

  1. Enter resistance values (in ohms) for each resistor — add up to 10.
  2. The tool sums all values: R_total = R1 + R2 + ... + Rn.
  3. Optionally enter a supply voltage to calculate circuit current (I = V / R_total).
  4. Voltage drop across each resistor is computed as V_n = I × R_n.
  5. Results update instantly as you type.

Use cases

  • Verify a resistor ladder design before breadboarding.
  • Calculate current limiting resistors for LED strings.
  • Check voltage divider ratios for sensor bias circuits.
  • Quickly sum resistor values when exact parts are unavailable.
  • Teach or demonstrate series-circuit fundamentals.

Frequently Asked Questions

Last updated: 2026-06-11 · Reviewed by Nham Vu