Free Online Resistor Color Calculator
How to Use the 4-Band Resistor Color Code Calculator
The 4-band resistor color code calculator is a simple tool that helps you quickly decode the value of any standard 4-band resistor.
- Select the First Color Band (1st Digit): Use the dropdown to choose the color of the first band on your resistor. This represents the first significant digit.
- Select the Second Color Band (2nd Digit): Pick the color of the second band. This gives the second significant digit of the resistance value.
- Select the Multiplier Band: The third color band is the multiplier, which determines how many zeros are added to the value.
- Choose the Tolerance Band: The fourth band indicates the tolerance (accuracy) of the resistor, typically shown as a percentage.
4-Band Resistor Color Code Calculator
Understanding Resistor Color Bands: 4-Band, 5-Band, and 6-Band Explained
Resistor color codes are a standard method for identifying resistor values using colored bands. Most resistors feature 4, 5, or 6 bands, each providing specific information such as resistance, tolerance, and temperature coefficient.
The more bands a resistor has, the more precise the value. For example:
- A 6-band resistor adds a sixth band to indicate the temperature coefficient.
- A 4-band resistor offers two significant digits, a multiplier, and a tolerance.
- A 5-band resistor includes an extra digit for better precision.
Band Breakdown by Type
| Band Position | 4-Band Meaning | 5-Band Meaning | 6-Band Meaning |
|---|---|---|---|
| 1st Band | 1st significant digit | 1st significant digit | 1st significant digit |
| 2nd Band | 2nd significant digit | 2nd significant digit | 2nd significant digit |
| 3rd Band | Multiplier | 3rd significant digit | 3rd significant digit |
| 4th Band | Tolerance | Multiplier | Multiplier |
| 5th Band | — | Tolerance | Tolerance |
| 6th Band | — | — | Temperature coefficient (tempco) |
Resistor Color Code Chart: Digit Values
Colors on the first few bands (significant digits) represent numeric values. Here’s a chart of common resistor color codes and their associated values:
| Color | Value |
|---|---|
| Black | 0 |
| Brown | 1 |
| Red | 2 |
| Orange | 3 |
| Yellow | 4 |
| Green | 5 |
| Blue | 6 |
| Violet | 7 |
| Grey | 8 |
| White | 9 |
Mnemonic Tip
Use this to memorize the order: Black, Brown, Red, Orange, Yellow, Green, Blue, Violet, Grey, White
Multiplier Color Code Table
The multiplier band (3rd for 4-band, 4th for 5- and 6-band) determines how many zeros are added to the base value:
| Color | Multiplier |
|---|---|
| Black | ×1 |
| Brown | ×10 |
| Red | ×100 |
| Orange | ×1,000 |
| Yellow | ×10,000 |
| Green | ×100,000 |
| Blue | ×1,000,000 |
| Violet | ×10,000,000 |
| Grey | ×100,000,000 |
| White | ×1,000,000,000 |
Quick Tip
The number of zeros in the multiplier is equal to the color’s digit value.
Tolerance Color Code Table
The tolerance band (4th for 4-band resistors, 5th for 5- and 6-band resistors) defines the acceptable variance in resistance:
| Color | Tolerance |
|---|---|
| Brown | ±1% |
| Red | ±2% |
| Orange | ±3% |
| Yellow | ±4% |
| Green | ±0.5% |
| Blue | ±0.25% |
| Violet | ±0.10% |
| Grey | ±0.05% |
| Gold | ±5% |
| Silver | ±10% |
| Black, White, Grey | N/A (not used for tolerance) |
Temperature Coefficient (Tempco) Values – 6-Band Only
The 6th band on a 6-band resistor indicates the temperature coefficient, showing how much resistance changes with temperature. It’s measured in ppm/°C (parts per million per degree Celsius).
| Color | Tempco (ppm/°C) |
|---|---|
| Brown | 100 |
| Red | 50 |
| Orange | 15 |
| Yellow | 25 |
| Blue | 10 |
| Violet | 5 |
| Others | N/A |
Resistor Color Code Exceptions
While most resistors follow standard color coding, there are exceptions worth noting:
5-Band Resistors with Gold or Silver in the 4th Band
This configuration is common in older or specialty resistors. The layout is:
- 1st–2nd: significant digits
- 3rd: multiplier
- 4th: tolerance (gold/silver)
- 5th: temperature coefficient
Substituting Gold/Silver in High-Voltage Resistors
To avoid conductive contamination, yellow and grey bands are sometimes used instead of gold and silver on high-voltage components.
Single Black Band – Zero Ohm Resistor
A resistor with only one black band is a 0Ω resistor—essentially a wire link in resistor form. It allows automated PCB placement just like other components.
Military-Grade Resistors with Reliability Band
Certain resistors made to military specifications include an additional band for reliability. This band indicates the failure rate (typically in % per 1000 hours of operation). Refer to MIL-HDBK-199 for official documentation.
Learning resistor color codes is essential for anyone working with electronics. Use the tables above to decode values manually, or simplify the process using our interactive Resistor Color Code Calculator.
Frequently Asked Questions (FAQ)
How do you read resistor color codes?
Each band on a resistor represents a number. The first two bands indicate digits, the third is the multiplier, and the fourth shows tolerance. This calculator decodes them for you.
What do the resistor color bands mean?
Colors represent numbers: Black (0), Brown (1), Red (2), Orange (3), Yellow (4), Green (5), Blue (6), Violet (7), Gray (8), White (9). Gold and silver represent multipliers and tolerance values.
Why are resistor color codes used?
Color bands are space-saving, durable, and readable without printing. They’re especially useful on small components where printed text is not practical.
What does the tolerance band on a resistor mean?
Tolerance tells you how much the resistor’s actual value may vary. For example, ±5% tolerance on a 100Ω resistor means the real resistance could be anywhere between 95Ω and 105Ω.
Is there an easier way to calculate resistor values?
Yes — this free tool automates the process. Just select the colors and instantly get the resistance value and tolerance, without needing to memorize the color code chart.
