Is parallel resistance always smaller?

Yes. The equivalent resistance of parallel branches is lower than the smallest individual branch resistance.

Why use parallel resistors?

Parallel resistors can create a lower value, split current, increase total power handling or approximate a nonstandard resistance.

Can the result be zero?

A zero-ohm branch acts like a short in the ideal model, so the equivalent resistance is effectively zero.

Parallel Resistor Calculator

Calculate equivalent resistance for resistors in parallel and find practical two-resistor combinations for a target value.

The equivalent resistance of a parallel network is always lower than the smallest branch value. With a voltage set, check branch current and power dissipation.

Resistors (for example 4.7k, 1M, 220)

Use decimal ohms for very small values, for example 0.1.

Branch 1100 ohm

Branch 2220 ohm

Branch 3330 ohm

Voltage, V (optional)

Equivalent resistance in parallel

Parallel resistor search intent is usually direct: enter two or more branch resistances and get the equivalent resistance, branch currents and power split.

\frac{1}{R _{e q}} = i = 1 \sum n \frac{1}{R _{i}}

Each branch contributes conductance to the total.

R_{e q} = \frac{R _{1} R _{2}}{R _{1} + R _{2}}

Shortcut for two parallel resistors.

Choosing a practical pair

When a nonstandard resistance is needed, two common values in parallel can often get close while sharing current and heat.

Package rating

Do not assume the power is shared equally unless the branch resistances are equal. Check each resistor's dissipation.

Frequently Asked Questions

Sources and References

Calculations are based on the listed reference sources. Links open in a new tab.

Updated: June 2, 2026

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