Resistor Color Code Calculator

Decode resistor color bands

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Number of Bands

Resistance--

Tolerance--

How to Use Resistor Color Code Calculator

Select bands

Choose colors for each band.

View value

See resistance in ohms.

Reverse

Or enter value to see colors.

Why Choose AllTools Resistor Color Code Calculator?

✓ 4 and 5 band
✓ Visual color display
✓ Tolerance band
✓ Reverse lookup
✓ Standard values
✓ No data stored

Why Use This Tool

★ All calculations happen locally in your browser
★ Completely free with no usage limits
★ No account or registration required
★ Based on established scientific formulas and constants
★ Works on any device with a modern browser

Related Resources

Ohms law calculator → LED resistor → Voltage divider →

Frequently Asked Questions

How do I read resistor bands? ▼

Hold resistor with tolerance band (gold/silver) on right. Read colors left to right: digit, digit, multiplier, tolerance.

What is the tolerance band? ▼

The tolerance band (usually gold or silver) indicates accuracy. Gold means +/-5%, silver means +/-10%, and no band means +/-20%.

Does this work on mobile? ▼

Yes. All AllTools tools are fully responsive and work on phones and tablets.

Guides

Free Science Tools -- Ohm's Law, Resistor Calculator, and More

Calculate Ohm's law, decode resistor colors, convert scientific units. Free browser tools for students and engineers.

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