Resistor Calculator
Decode resistor color bands to find resistance values.
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Resistor Color Code Calculator
Resistor Color Code Calculator
Resistors use colored bands to indicate their resistance value and tolerance. A resistor color code calculator decodes these bands to find the exact resistance (in ohms) and tolerance percentage, or encodes a resistance value into its color band combination.
Common Uses
- Reading resistor values from color bands in electronics projects
- Ordering the correct resistors for a circuit
- Electronics education and learning
- Quality control and verification in manufacturing
Frequently Asked Questions
How do I read a 4-band resistor?
4-band resistors: Band 1 = first digit, Band 2 = second digit, Band 3 = multiplier (×10^n), Band 4 = tolerance. Example: Brown (1), Black (0), Red (×100), Gold (±5%) = 1,000 Ω ±5% (1 kΩ).
What does tolerance mean on a resistor?
Tolerance indicates how close the actual resistance is to the marked value. Gold band = ±5%, Silver = ±10%, No band = ±20%. A 1kΩ ±5% resistor has an actual value between 950Ω and 1,050Ω. For precision circuits, use 1% tolerance (brown band) resistors.
Is this calculator free to use?
Yes. All calculators on zenicalculator.com are completely free with no registration required.
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