Resistor Color Code Calculator
Quickly decode 4/5/6-band resistors and SMD codes
3-Digit: First two are significant figures, third is multiplier (e.g., 103 = 10×10³ = 10kΩ)
4-Digit: First three are significant figures, fourth is multiplier (e.g., 4702 = 470×10² = 47kΩ)
R-notation indicates decimal point (e.g., R47 = 0.47Ω, 4R7 = 4.7Ω)
Enter a resistance to find its color code
E-Series Reference (IEC 60063)
About Resistor Color Code Calculator
The Resistor Color Code Calculator is an essential tool for electronics engineers and hobbyists. This calculator supports 4, 5, and 6-band resistor color code conversion, as well as SMD surface-mount resistor code lookup. All calculations follow the IEC 60062 international standard.
How to Use the Resistor Color Code Calculator
- Select resistor type (4/5/6-band) or switch to SMD mode
- Click color blocks to select each band color, or enter the SMD code
- The answer banner above instantly shows the resistance value, tolerance range, and a plain-language note
- Use "Value to Bands" to reverse lookup color codes
Resistor Color Code Chart
| Color | Digit | Multiplier | Tolerance | TCR |
|---|---|---|---|---|
| Black | 0 | ×1 | - | 250 |
| Brown | 1 | ×10 | ±1% | 100 |
| Red | 2 | ×100 | ±2% | 50 |
| Orange | 3 | ×1k | - | 15 |
| Yellow | 4 | ×10k | - | 25 |
| Green | 5 | ×100k | ±0.5% | 20 |
| Blue | 6 | ×1M | ±0.25% | 10 |
| Violet | 7 | ×10M | ±0.1% | 5 |
| Gray | 8 | ×100M | ±0.05% | 1 |
| White | 9 | ×1G | - | - |
| Gold | - | ×0.1 | ±5% | - |
| Silver | - | ×0.01 | ±10% | - |
Frequently Asked Questions
Q: How do I determine the reading direction of a resistor?
For 4-band resistors, the gold or silver tolerance band is usually on the right. For 5 and 6-band resistors, the first band is closer to the resistor's edge. If uncertain, try both directions and choose the more reasonable standard value.
Q: What are E-series standard values?
E-series are standard resistor values defined by IEC 60063. E12 has 12 values (±10% tolerance), E24 has 24 values (±5%), and E96 has 96 values (±1%). Values are logarithmically spaced to ensure any resistance can find a nearby standard resistor.
Q: What SMD resistor code formats are there?
There are three main formats: (1) 3-digit format (e.g., 103 = 10kΩ); (2) 4-digit format (e.g., 4702 = 47kΩ); (3) EIA-96 format (e.g., 01A = 100Ω). R-notation indicates decimal point position (e.g., R47 = 0.47Ω).
Q: What does the 6th band on a resistor represent?
The sixth band indicates the temperature coefficient (TCR), measured in ppm/°C. Brown is 100ppm/°C, red is 50ppm/°C. Lower TCR values mean the resistor is more stable with temperature changes.
Reference Standards
- IEC 60062: Marking codes for resistors and capacitors
- IEC 60063: Preferred number series for resistors and capacitors (E-series)
- EIA-96: SMD resistor marking standard
This calculator is developed based on IEC 60062 and EIA-96 standards. For reference only.
