Calculate equivalent resistance, total current, branch currents, voltage drops, power, and conductance for series, parallel, or mixed circuits with clear step-by-step results and exports.
Calculated values appear here before the input form.
| Element | Resistance | Voltage | Current | Power | Share / Contribution |
|---|
Series: Req = R1 + R2 + ... + Rn.
Parallel: 1/Req = 1/R1 + 1/R2 + ... + 1/Rn.
Current: I = V / Req.
Power: P = VI. Conductance: G = 1/Req.
Equivalent resistance replaces several resistors with one matching resistance. This simplification helps describe how a source sees the circuit. In a series network, every resistor carries identical current. Their resistance values add directly to form total resistance. Higher series resistance reduces current for a fixed voltage. Voltage divides according to each resistor's share of resistance.
Parallel resistors share the same voltage across every branch. Their branch currents depend on individual resistance values. Lower resistance branches carry more current than higher branches. Total current equals the sum of branch currents. Equivalent parallel resistance stays below the smallest branch resistance. This behavior follows the reciprocal resistance relationship.
Mixed circuits combine series paths with parallel resistor groups. This calculator treats each comma group as parallel. Semicolons then connect those groups in series. Each group first receives its own equivalent resistance. Those group resistances are added for the network total. Source current follows from Ohm's law after simplification.
Current measures electric charge flow through the equivalent network. Power describes the electrical energy converted each second. Conductance describes how easily the network carries electric current. It is the reciprocal of equivalent resistance. Component power helps estimate heating within individual resistors. Real resistors need suitable power ratings for safe operation.
Calculated values assume ideal resistors and steady source voltage. Practical circuits can vary because components have tolerances. Leads, contacts, and temperature may change measured resistance slightly. Very low resistance can create extremely large calculated currents. Always compare calculated current with actual source limits. Measurement instruments also introduce small loading effects during testing. Battery voltage may fall when current demand rises sharply. Resistor temperature coefficients can shift resistance during operation. These factors explain differences between theoretical and measured results. Choose suitable resistor wattage before building practical test circuits. Use clear inputs to obtain dependable circuit estimates quickly.
| Voltage | Circuit | Resistors | Equivalent Resistance | Total Current |
|---|---|---|---|---|
| 12 V | Series | 10 Ω, 20 Ω | 30 Ω | 0.4 A |
| 12 V | Parallel | 10 Ω, 20 Ω | 6.667 Ω | 1.8 A |
| 24 V | Series | 5 Ω, 15 Ω, 20 Ω | 40 Ω | 0.6 A |
| 10 V | Parallel | 10 Ω, 10 Ω | 5 Ω | 2 A |
It is one resistance producing the same circuit behavior.
Parallel branches create additional paths for electric current.
Yes. Ideal series components carry the same current.
Yes. Every ideal parallel branch has equal voltage.
Commas create parallel groups. Semicolons connect groups in series.
Yes. Use the CSV and PDF download buttons.
Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.