What is a resistor color code?

A resistor color code is a system of colored bands printed on a resistor body that encodes its resistance value and tolerance. The Electronic Industries Alliance (EIA) standardized this system so engineers can read component values without a meter.

How do I read a 4-band resistor?

On a 4-band resistor the first two bands are significant digits, the third band is a multiplier (power of ten), and the fourth band is the tolerance. For example: Yellow-Violet-Red-Gold = 4700 ohms ± 5%.

How do I read a 5-band resistor?

On a 5-band resistor the first three bands are significant digits, the fourth is a multiplier, and the fifth is the tolerance. 5-band resistors are used for precision components with tighter tolerances (1% or 2%).

What does the gold or silver band mean?

Gold means the actual resistance is within ±5% of the stated value, and silver means ±10%. These appear as the last band and indicate how precisely the resistor was manufactured.

Which end do I start reading from?

Start from the end closest to the first significant-digit band. The tolerance band (gold, silver, or brown for 1%) is usually set farther apart from the others, making the starting end easier to identify.

What if my resistor value shows in kilohms or megaohms?

This calculator shows the result in ohms and automatically converts to kilohms (kΩ) or megaohms (MΩ) when the value is large enough, so you can read it at a glance.

Resistor Color Code Calculator

Select resistor color bands to instantly decode the resistance value and tolerance in ohms.

Select Color Bands

Band 1

Band 2

Band 3

Band 4

Decoded Result

Resistance

—

ohms

Tolerance

—

percent

Color Code Reference

Color	Digit	Multiplier	Tolerance

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Summary

The Resistor Color Code Calculator decodes the colored bands printed on resistors to reveal their resistance value in ohms and the tolerance percentage. Simply choose between a 4-band or 5-band resistor, select each band color, and the calculator instantly displays the decoded value. It supports all standard EIA color codes from black to white.

How it works

Choose whether your resistor has 4 or 5 color bands.
Select the color for each band using the dropdown menus.
The first two (or three) bands represent significant digits of the resistance.
The multiplier band shifts the value by a power of ten.
The final band indicates the tolerance — how far from the stated value the actual resistance may be.
The decoded resistance and tolerance are displayed instantly in ohms.

Use cases

Identify an unlabeled resistor pulled from a parts bin.
Verify a resistor value before soldering it onto a PCB.
Learn the EIA color code system as a student or hobbyist.
Cross-check a resistor reading when a multimeter is unavailable.
Decode vintage through-hole resistors during repair work.
Quickly confirm component values during circuit prototyping.

Frequently Asked Questions

Last updated: 2026-05-23 · Reviewed by Nham Vu