Resistor Color Code Calculator
Decode 4-band and 5-band resistor colour codes into resistance and tolerance range.
Step-by-step working
- Digits: brown, black
- Multiplier: red
- Tolerance: gold
Mathematical Formula
Overview & Explanation
Resistors are marked with coloured bands: 2 or 3 significant digits, a multiplier and a tolerance.
How It Works
- Read digit bands.
- Apply the multiplier.
- Apply tolerance to get min/max.
Practical Applications
- Electronics hobby projects.
- Checking parts before soldering.
Example 1: brown-black-red-gold
1 kΩ ±5%.
Inputs
Number of bands: 4 bands · Band 1 (digit): Brown (1) · Band 2 (digit): Black (0) · Multiplier band: Red (×10^2) · Tolerance band: Gold ±5%
Step 1
Digits: brown, black
Step 2
Multiplier: red
Step 3
Tolerance: gold
Resistance
Result
Example 2: yellow-violet-black-brown-brown
4.7 kΩ ±1% (5-band).
Inputs
Number of bands: 5 bands · Band 1 (digit): Yellow (4) · Band 2 (digit): Violet (7) · Band 3 (digit, 5-band only): Black (0) · Multiplier band: Brown (×10^1) · Tolerance band: Brown ±1%
Step 1
Digits: yellow, violet, black
Step 2
Multiplier: brown
Step 3
Tolerance: brown
Resistance
Result
How it's calculated & sources
R = (significant digits) × 10^multiplier; range = R × (1 ± tolerance). Colour values per IEC 60062.
Frequently Asked Questions
Which end do I start from?
What about 6-band resistors?
Mnemonic?
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