Calculate resistor values from color codes or find color codes for a specific resistance. Calculate series and parallel resistance combinations.
Resistance
1.00 kΩ
±5%
| Color | Digit | Multiplier | Tolerance |
|---|---|---|---|
| Black | 0 | ×1 | - |
| Brown | 1 | ×10 | ±1% |
| Red | 2 | ×100 | ±2% |
| Orange | 3 | ×1,000 | - |
| Yellow | 4 | ×10,000 | - |
| Green | 5 | ×100,000 | ±0.5% |
| Blue | 6 | ×1,000,000 | ±0.25% |
| Violet | 7 | ×10,000,000 | ±0.1% |
| Gray | 8 | ×100,000,000 | ±0.05% |
| White | 9 | ×1,000,000,000 | - |
| Gold | - | ×0.1 | ±5% |
| Silver | - | ×0.01 | ±10% |
Read bands from left to right, starting from the band closest to one end. First 2-3 bands are significant digits, next is multiplier, then tolerance. For a 4-band: Brown-Black-Red-Gold = 10 × 100 = 1kΩ ±5%.
4-band: 2 digits + multiplier + tolerance (standard). 5-band: 3 digits + multiplier + tolerance (precision). 6-band: adds temperature coefficient. More bands = higher precision.
Tolerance indicates how much the actual value can vary from the marked value. A 1kΩ ±5% resistor can range from 950Ω to 1050Ω. Lower tolerance = more precise = more expensive.
Series: add values (R_total = R1 + R2). Parallel: 1/R_total = 1/R1 + 1/R2. Series increases resistance, parallel decreases it. Two equal resistors in parallel = half the resistance.
The first band is usually closer to one end. Tolerance band (Gold/Silver) is always last and helps identify direction. If both ends look similar, the wider gap is before the tolerance band.
Resistance
1.00 kΩ
±5%