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Series resistance calculator

For resistors in series, add the resistance values.

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Answer

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For resistors in series, add the resistance values.

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Precision and calculation record
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Formula and assumptions
Enter nonnegative resistances in ohms. This ideal DC calculation excludes temperature changes and parasitic effects.
In a list, use spaces, new lines, semicolons, or commas followed by a space. A comma between groups of three digits is a thousands separator.
Automatic precision shows numbers to 12 significant digits. Thousands separators such as 1,000 are accepted; use a dot for decimals.
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Using Series resistance calculator
For resistors in series, add the resistance values.
Enter nonnegative resistances in ohms. This ideal DC calculation excludes temperature changes and parasitic effects.
Next: Basic calculator
A worked example
With resistances (ohms) = 10 20 20, the equivalent resistance (ohms) is 50.
Before you use the result
Enter nonnegative resistances in ohms. This ideal DC calculation excludes temperature changes and parasitic effects.
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ToolOctopus. “Series resistance calculator.” Updated 2026-09-26. https://tooloctopus.com/series-resistance-calculator.
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