Resistor Color Code Calculator (4/5/6 band)
Visual 4, 5 and 6-band resistor decoder with live colour preview, tolerance range and temperature coefficient — IEC 60062.
Resistor Color Code Calculator computes the resistance, tolerance and tempco encoded in a resistor's colour bands — free, instant and private in your browser. Students, repair techs and makers reading through-hole resistors at the bench use it to skip the datasheet algebra: type your numbers, read the answer with the substituted formula shown step by step, and share an exact permalink of the calculation.
About Resistor Color Code Calculator (4/5/6 band)
Resistor Color Code Calculator computes the resistance, tolerance and tempco encoded in a resistor's colour bands using the standard engineering relation: R = (digit bands as a number) × multiplier band; tolerance and tempco from their own bands (IEC 60062). Worked live: brown-black-red-gold reads 10 × 100 = 1 kΩ ±5 %. The result recalculates on every keystroke, the worked-example panel shows your numbers substituted into the formula, and the Copy permalink button encodes the inputs in the URL so a colleague opens exactly your calculation. Everything runs client-side — nothing you type leaves your device.
How to use Resistor Color Code Calculator (4/5/6 band)
- 1Enter your values — the tool starts with realistic defaults for this exact use case, so the worked example is meaningful immediately.
- 2Read the live result and the worked-example panel, which substitutes your numbers into the formula step by step.
- 3Adjust any input to compare scenarios, then use Copy result or Copy permalink to share the calculation.
Why use Resistor Color Code Calculator (4/5/6 band)?
- ✓Implements the real formula — R = (digit bands as a number) × multiplier band — with the substitution shown, not a black box
- ✓Built for students, repair techs and makers reading through-hole resistors at the bench
- ✓Copy result and permalink buttons — share the exact calculation in a README, forum answer or design review
- ✓100% free, no sign-up, runs entirely in your browser (works offline once loaded)
Frequently asked questions
How do you calculate resistor color code?+
The resistance, tolerance and tempco encoded in a resistor's colour bands follows R = (digit bands as a number) × multiplier band; tolerance and tempco from their own bands (IEC 60062). For example, brown-black-red-gold reads 10 × 100 = 1 kΩ ±5 %. The calculator applies the same relation and shows the substituted arithmetic so you can verify every step.
Which end of the resistor do I read from?+
Start from the band nearest an end; the tolerance band (gold/silver, often separated by a wider gap) goes on the right. If a 5-band reading gives a weird non-standard value, flip it and read the other way — the correct direction yields an E-series value.
What's the difference between 4-band and 5-band codes?+
4-band parts encode two significant digits (±5/±10 % carbon film); 5-band parts add a third digit for ±1 % metal film. The 6th band, when present, is the temperature coefficient in ppm/°C.
Is the Resistor Color Code Calculator free and private?+
Yes — completely free with no sign-up or usage limits, and it runs entirely in your browser: the values you enter are never uploaded or stored on a server.
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