Resistor Color Code Calculator
Free online resistor color code calculator. Read resistance from 4, 5, or 6 color bands per IEC 60062, with tolerance and temperature coefficient, and reverse-look-up bands from any ohm value. 100% client-side, no signup.
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What is Resistor Color Code Calculator?
A Resistor Color Code Calculator is a free online tool that reads the resistance value of a through-hole resistor from its painted color bands, following the IEC 60062 standard. You choose the number of bands (4, 5, or 6), pick each color, and the tool instantly computes the resistance, tolerance range, and (for 6-band resistors) the temperature coefficient. A built-in reverse mode also finds the digit and multiplier bands you need to reach any target ohm value. Everything runs in your browser, so your work stays private.
Key Benefits
- Decodes 4, 5, and 6 band resistors per IEC 60062
- Live color-band preview that updates as you select colors
- Shows tolerance range (min–max) and temperature coefficient
- Reverse lookup converts any ohm value to the required bands
- 100% client-side and private — no account or data upload
Common Use Cases
- •Identifying an unmarked resistor pulled from a parts bin
- •Checking whether a resistor is safe to use in a circuit before soldering
- •Teaching students how the color code maps to digits, multiplier, and tolerance
- •Finding the right bands to hit a target resistance in a DIY electronics project
- •Verifying tolerance range for precision analog or measurement circuits
How to Use the Resistor Color Code Calculator
- Choose the Band Count: Pick 4, 5, or 6 bands at the top. Most through-hole resistors use 4 bands; precision resistors often use 5 or 6 with an extra digit and/or a temperature coefficient band.
- Select Each Color: Use the color dropdowns to set every band, left to right, as printed on the resistor. The visual preview updates live, and invalid colors are blocked from digit and multiplier bands.
- Read the Result: The big number shows resistance (Ω, kΩ, MΩ, or GΩ), followed by the tolerance percentage, the min–max range, and (for 6-band) the temperature coefficient in ppm/°C.
- Reverse Lookup (Optional): Enter a target ohm value and unit in the Reverse box to instantly see the digit and multiplier color bands you need to hit that resistance.
Key Features
- Decodes 4, 5, and 6 band resistors with a live color-band preview.
- Full IEC 60062 color set including gold, silver, and no-band tolerance.
- Shows tolerance range (min–max) and temperature coefficient in ppm/°C.
- Reverse mode converts any ohm value back to the digit and multiplier bands.
- Auto-formats results in Ω, kΩ, MΩ, and GΩ for easy reading.
- Copy the full resistance summary to clipboard in one click.