Read any 3–6 band resistor with confidence
This free resistor color code calculator converts axial resistor bands to ohms, tolerance range and, for six-band parts, temperature coefficient. Switch to Find bands from resistance to perform the reverse lookup without losing the resistor already on screen.
How to read resistor colour bands
- Find the reading direction. The tolerance band is usually separated by a wider gap and commonly appears gold, silver or another tolerance colour. Read from the opposite end.
- Select the band count. Three- and four-band resistors use two significant digits; five- and six-band resistors use three.
- Choose each colour from left to right. Wirecora updates the realistic resistor, resistance and tolerance limits immediately.
- Check the physical part when safety matters. Faded paint and lighting can mislead; confirm uncertain values with a calibrated multimeter.
Which end comes first?
Black is digit 0 and may appear as a leading black band in a multi-band code. It is uncommon in the first position because a leading zero adds no precision. A separated tolerance band normally sits at the right-hand end; gold and silver are never significant digits.
A zero-ohm jumper is a separate component marking, usually one centred black band. It is not a normal all-black 3-, 4-, 5- or 6-band resistance code.
Resistor band and accuracy guides
Open the guide that matches the part on your bench, or review tolerance and temperature behavior.
3, 4, 5 and 6-band resistor guide
More bands add precision and, with a sixth band, temperature information. They do not change the basic significant-digits × multiplier formula.
| Type | Significant digits | Multiplier | Tolerance | Temperature coefficient |
|---|---|---|---|---|
| 3 bands | 2 digits | Band 3 | No band: ±20% | — |
| 4 bands | 2 digits | Band 3 | Band 4 | — |
| 5 bands | 3 digits | Band 4 | Band 5 | — |
| 6 bands | 3 digits | Band 4 | Band 5 | Band 6 |
How the resistor calculation works
Resistance = significant digits × 10multiplier exponent Ω
Minimum = nominal × (1 − tolerance ÷ 100)
Maximum = nominal × (1 + tolerance ÷ 100)
For a six-band resistor, the last band is the temperature coefficient of resistance (TCR), expressed as ±parts per million per kelvin.
Tolerance range and TCR
A 1 kΩ ±5% resistor is expected to measure from 950 Ω to 1.05 kΩ at its specified reference conditions. A TCR of ±50 ppm/K means resistance may change by up to 0.005% per kelvin from the reference temperature.
The pink multiplier (×0.001), orange ±0.05%, yellow ±0.02% and gray ±0.01% values are rare but valid in the current IEC table.
Worked resistor colour-code examples
These examples are generated with the same calculation engine as the live tool.
220 Ω ±5%
Red · Red · Brown · Gold
22 × 10¹209 Ω to 231 Ω4.7 kΩ ±5%
Yellow · Violet · Red · Gold
47 × 10²4.465 kΩ to 4.935 kΩ12.3 kΩ ±1%
Brown · Red · Orange · Red · Brown
123 × 10²12.177 kΩ to 12.423 kΩ68 kΩ ±1%
Blue · Gray · Black · Red · Brown · Red
680 × 10² · TCR ±50 ppm/K67.32 kΩ to 68.68 kΩCommon 4-band resistor colour codes
Popular values are generated from the same reverse encoder as the calculator, using a gold ±5% tolerance band.
| Resistance | Band sequence, read left to right | Tolerance |
|---|---|---|
| 100 Ω | Brown · Black · Brown · Gold | ±5% |
| 220 Ω | Red · Red · Brown · Gold | ±5% |
| 330 Ω | Orange · Orange · Brown · Gold | ±5% |
| 470 Ω | Yellow · Violet · Brown · Gold | ±5% |
| 1 kΩ | Brown · Black · Red · Gold | ±5% |
| 2.2 kΩ | Red · Red · Red · Gold | ±5% |
| 4.7 kΩ | Yellow · Violet · Red · Gold | ±5% |
| 10 kΩ | Brown · Black · Orange · Gold | ±5% |
| 100 kΩ | Brown · Black · Yellow · Gold | ±5% |
| 1 MΩ | Brown · Black · Green · Gold | ±5% |
Popular resistor values
Open a worked color-code page generated from the same resistor engine as the calculator.
Common resistor reading mistakes
Reading backwards
Look for the wider gap before the tolerance band and begin at the opposite end.
Gold versus yellow
Gold is metallic and reflective; yellow is a solid paint colour. Gold is a multiplier or tolerance, never a digit.
Silver versus gray
Silver is metallic and is used for ×0.01 or ±10%. Gray is a digit and can also represent tolerance or TCR.
Assuming every value is exact
Reverse lookup can return the nearest representable band code. The tool clearly labels that case.
Resistor colour code FAQ
What is the difference between a 4-band and 5-band resistor?
A four-band resistor has two significant digits; a five-band resistor has three, so it can identify more precise nominal values.
What does the sixth resistor band mean?
The sixth band is TCR. It describes how much resistance may shift with temperature, in ±ppm/K.
What does a leading black band mean?
Black is digit 0 in a multi-band code. Manufacturer calculators accept it in the first position, although it is uncommon because the leading zero is redundant. A component with only one centred black band is instead a nominal zero-ohm jumper.
Is pink a real resistor band colour?
Yes. IEC 60062 added pink as the rare ×0.001 multiplier. Many simplified manufacturer charts omit values they do not use.
Can I download the resistor image?
Yes. The clean PNG keeps a transparent background; the labelled guide adds role arrows and Wirecora attribution for sharing.
Should I trust colour bands for repair work?
Use them to identify the intended value, then verify uncertain or safety-critical parts with proper test equipment.
Calculation and verification methodology
Band roles follow IEC 60062:2016+A1:2019. Manufacturer guidance from Panasonic Industry and Vishay is used as a practical cross-check. The calculator uses deterministic arithmetic, not AI estimation.
Logic verification: 25,740 canonical 3–6 band encode/decode combinations tested.