Resistor Color Code Calculator
Decode 4-, 5- and 6-band resistor colour codes into resistance, tolerance range and temperature coefficient.
Your inputs
Results
Resistance
1 kΩ
- In ohms
- 1,000 Ω
- Tolerance
- ±5 %
- Range
- 950 Ω – 1.05 kΩ
- Temperature coefficient
- —
✓Exact calculation — rounded only for display
What this calculator does
Through-hole resistors are marked with coloured bands. The first bands are digits, then a multiplier, tolerance and (for 6 bands) temperature coefficient.
Formula and method
Worked example
Calculated by this tool with its default inputs:
Inputs
- Number of bands: 4 bands
- Band 1 (digit): Brown (1)
- Band 2 (digit): Black (0)
- Multiplier band: Red (×100)
- Tolerance band: Gold (±5 %)
Results
- Resistance: 1 kΩ
- In ohms: 1,000 Ω
- Tolerance: ±5 %
- Range: 950 Ω – 1.05 kΩ
- Temperature coefficient: —
How to read the results
The tolerance range shows the minimum and maximum actual resistance.
Assumptions and limitations
- Colour standard IEC 60062.
These are educational estimates. Electrical, structural and other safety-critical work must comply with local codes and be designed or checked by a qualified professional.
Questions
Which end do I read from?
The tolerance band (often gold or silver) is usually set apart at the right-hand end.
Methodology and verification
- Result type
- Exact mathematical calculation (rounded only for display)
- Formula version
- 1.0
- Automated verification
- 4 reference and validation test cases, checked against independently computed values. The site cannot be built if any of them fail.
- Editorial review
- Awaiting human editorial review. The explanation was drafted with AI assistance; the formula and examples are verified by the automated tests above.
Privacy
Everything you enter is calculated in this browser and is not sent to Numerith or anyone else. Inputs are added to a share link only if you choose to include them. Privacy policy