Free online tool

Resistor Color Code Calculator

Choose colored bands and read the resistance in ohms, kilohms, or megohms.

Resistance-
Tolerance range-

Method

Technical calculation method

The tool uses deterministic browser APIs and standard numeric or data-format rules. Inputs and outputs remain visible so addresses, dimensions, codes, and serialized data can be checked directly.

Network and hardware results follow the selected CIDR, band, pixel, or format values; verify production settings against the target system specification.

Questions

Resistor Color Code Calculator FAQ

How are resistor color bands read?

Significant-digit bands come first, followed by a multiplier and then a tolerance band.

Which end of a resistor is read first?

The tolerance band is often spaced farther from the other bands and is read last.

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