Series Parallel Resistors Calculator

Calculator Inputs

Network Type

Use mixed mode for parallel branches made of series resistor chains.

Source Voltage (V)

This voltage is applied across the full network.

Decimal Places

Choose display precision for all outputs.

Graph Metric

The graph updates after each calculation.

Load Example Data

Example buttons populate the form with ready-to-test values.

Resistor Values for Series or Parallel (Ω)

Separate values with commas, spaces, or new lines.

Series-Parallel Branch Layout (Ω)

Each line is one parallel branch. Values inside each line are series resistors.

Example Data Table

Case	Mode	Input Layout	Source Voltage	What It Demonstrates
Example 1	Series	10, 22, 47	12 V	Same current through each resistor, different voltage drops.
Example 2	Parallel	10, 22, 47	12 V	Same voltage across each resistor, different branch currents.
Example 3	Series-Parallel	10, 20 / 30, 40, 50 / 60, 15	24 V	Parallel branches made from series resistor chains.

Formula Used

1) Series Network

Equivalent resistance: R_eq = R₁ + R₂ + R₃ + ...

Total current: I = V / R_eq

Voltage drop on each resistor: V_n = I × R_n

2) Parallel Network

Equivalent resistance: 1 / R_eq = 1 / R₁ + 1 / R₂ + 1 / R₃ + ...

Branch current: I_n = V / R_n

Total current: I_total = I₁ + I₂ + I₃ + ...

3) Series-Parallel Network

First, add resistors inside each branch because those branch elements are in series.

Branch resistance: R_branch = sum of branch resistors

Next, combine all branch resistances using the parallel formula.

Power: P = V × I, or P = I²R, or P = V² / R

How to Use This Calculator

Select the network type: series, parallel, or series-parallel.
Enter the source voltage applied across the full resistor network.
For series or parallel mode, type resistor values in one box.
For mixed mode, enter one branch per line.
Inside each branch line, separate resistor values with commas or spaces.
Choose decimal places and the graph metric you want to review.
Press Calculate to show total values, branch details, resistor details, and the graph.
Use the export buttons to save your results as CSV or PDF.

FAQs

1) What does this calculator compute?

It calculates equivalent resistance, total current, total power, branch values, and individual resistor voltage, current, and power for supported resistor network layouts.

2) Which mixed circuits does it support?

It supports a common mixed arrangement where each branch contains series resistors, and those branches are connected in parallel across the source.

3) Why is source voltage required?

Source voltage is necessary to compute current, voltage drop, and power. Without it, only equivalent resistance could be determined.

4) Can I use decimal resistor values?

Yes. The calculator accepts decimal values such as 2.2, 4.7, 10.5, and other positive numeric resistor values.

5) How are branch values calculated in mixed mode?

Each branch resistance is found by summing series resistors in that branch. Then all branch resistances are combined using the parallel resistance formula.

6) What does the graph show?

The graph displays resistor-by-resistor voltage, current, or power values, depending on the graph option you selected before calculation.

7) When should I export CSV or PDF?

CSV is helpful for spreadsheets and further analysis. PDF is useful for reports, records, classroom notes, and quick sharing.

8) Are zero or negative resistor values allowed?

No. This calculator requires all resistor values to be greater than zero to keep the electrical calculations valid.