Translate bands into resistance values instantly
Supports 4-band, 5-band, and 6-band resistor colour codes. See the nominal resistance, tolerance, and temperature coefficient (for 6-band) as you pick colours, plus the closest preferred E-series values. The reverse lookup mode suggests colour bands from a target resistance.
- 1Bidirectional colour ↔ value solver with live updates
- 2Shareable URLs and local favourites for frequent combos
- 3Nearest E24 / E96 picks for procurement-friendly values
- 4Touch-friendly swatch UI tuned for phones and tablets
Reference table
Not every colour is valid for every band. Temperature coefficients apply to precision 6-band resistors.
| Colour | Digit | Multiplier | Tolerance | Temp. coefficient |
|---|---|---|---|---|
| Black | 0 | ×100 | — | 250 ppm/K |
| Brown | 1 | ×101 | ±1% | 100 ppm/K |
| Red | 2 | ×102 | ±2% | 50 ppm/K |
| Orange | 3 | ×103 | ±3% | 15 ppm/K |
| Yellow | 4 | ×104 | ±4% | 25 ppm/K |
| Green | 5 | ×105 | ±0.5% | 20 ppm/K |
| Blue | 6 | ×106 | ±0.25% | 10 ppm/K |
| Violet | 7 | ×107 | ±0.1% | 5 ppm/K |
| Gray | 8 | ×108 | ±0.05% | 1 ppm/K |
| White | 9 | ×109 | — | 0.5 ppm/K |
| Gold | — | ×10-1 | ±5% | — |
| Silver | — | ×10-2 | ±10% | — |
| None | — | — | ±20% | — |
FAQ
Which band count should I choose?
Standard carbon film resistors are 4-band, metal film parts typically use 5 bands, and precision parts with thermal tracking add a 6th temperature coefficient band.
Can I derive colours from a value?
Yes. Use the “Value → Colours” tab, enter your value and tolerance, then submit to get a suggested colour code.
What are the E-series suggestions?
They show the nearest IEC preferred values (E24/E96) so you can match against commonly stocked resistors.
How it’s calculated
How it’s calculated