ToolBox.Online

Resistor Color Code Calculator — Decode Resistor Colors Online [2026]

Convert resistor color bands to resistance value (ohms/kΩ/MΩ) or enter a value to find color bands. Supports 4-band and 5-band resistors with tolerance. Free online resistance color code converter.

Resistor Visualization

1st2ndMulTol

Resistance Value

1 kΩ

±5% tolerance

Reverse: Value → Color Bands

Color Code Reference Table

ColorDigitMultiplierTolerance
Black
0×1—
Brown
1×10±1%
Red
2×100±2%
Orange
3×1,000—
Yellow
4×10,000—
Green
5×100,000±0.5%
Blue
6×1,000,000±0.25%
Violet
7×10,000,000±0.1%
Gray
8×100,000,000±0.05%
White
9×1,000,000,000—
Gold
—×0.1±5%
Silver
—×0.01±10%
None
——±20%

What is Resistor Color Code Calculator?

A resistor is a passive electronic component that limits or regulates the flow of electric current in a circuit. Resistors are marked with colored bands that encode their resistance value, multiplier, and tolerance according to an international standard color code system. The resistor color code system was developed to allow quick identification of resistance values without needing to measure each component. Each color represents a digit (0–9), a multiplier (×1 to ×1G), or a tolerance percentage. The system works for both 4-band resistors (two significant digits + multiplier + tolerance) and 5-band resistors (three significant digits + multiplier + tolerance), which offer higher precision. This calculator decodes those color bands into a human-readable resistance value and also works in reverse — enter a desired resistance and see which color bands to look for. This is essential for electronics hobbyists, students, and engineers who work with through-hole resistors.

How to Use Resistor Color Code Calculator

Select the number of bands (4 or 5) for your resistor. Choose a color for each band from the dropdown menus — the first 2 or 3 bands represent significant digits, the next band is the multiplier, and the last band is tolerance. The resistance value is calculated and displayed instantly in ohms, kilohms, or megohms. To use reverse mode, enter a resistance value in ohms and the tool will show you the correct color bands. A visual resistor diagram updates in real time as you make selections.

How Resistor Color Code Calculator Works

The resistor color code follows an international standard (IEC 60062) where each color maps to a digit, multiplier, or tolerance value: **Digits (Bands 1–2 or 1–3):** Black=0, Brown=1, Red=2, Orange=3, Yellow=4, Green=5, Blue=6, Violet=7, Gray=8, White=9 **Multiplier Band:** Black=×1, Brown=×10, Red=×100, Orange=×1k, Yellow=×10k, Green=×100k, Blue=×1M, Violet=×10M, Gray=×100M, White=×1G, Gold=×0.1, Silver=×0.01 **Tolerance Band:** Brown=±1%, Red=±2%, Green=±0.5%, Blue=±0.25%, Violet=±0.1%, Gray=±0.05%, Gold=±5%, Silver=±10%, None=±20% For a 4-band resistor, the formula is: (10×Band1 + Band2) × Multiplier ± Tolerance. For a 5-band resistor: (100×Band1 + 10×Band2 + Band3) × Multiplier ± Tolerance.

Common Use Cases

  • Identifying the resistance value of through-hole resistors by reading their color bands
  • Verifying resistor values before placing components on a breadboard or PCB
  • Finding the correct color band combination when shopping for specific resistance values
  • Teaching and learning electronics — understanding the resistor color code standard
  • Quickly converting between 4-band and 5-band resistor codes for different precision levels
  • Troubleshooting electronic circuits by confirming component values match the schematic

Frequently Asked Questions

How do I read a 4-band resistor color code?▼

On a 4-band resistor, the first two bands represent significant digits (tens and ones), the third band is the multiplier, and the fourth band is the tolerance. For example, Brown-Black-Red-Gold means 10 × 100 = 1,000Ω (1kΩ) with ±5% tolerance.

What is the difference between 4-band and 5-band resistors?▼

4-band resistors have two significant digit bands, one multiplier band, and one tolerance band. 5-band resistors add a third significant digit for higher precision. For example, a 4-band can specify values like 47kΩ, while a 5-band can specify 47.5kΩ.

Which direction do I read resistor color bands?▼

Read from the band closest to one end of the resistor. The tolerance band (usually gold or silver) is always the last band and is sometimes spaced slightly further from the other bands. If uncertain, the first band is never gold or silver.

What does the gold band on a resistor mean?▼

A gold band has different meanings depending on its position. As a tolerance band (last band), gold means ±5% tolerance. As a multiplier band, gold means ×0.1 (divide by 10), which is used for sub-1Ω resistor values.

Can this tool convert a resistance value to color bands?▼

Yes. Enter your desired resistance value in ohms in the reverse calculator section, and the tool will display the corresponding color band combination for both 4-band and 5-band resistors.

What are the most common resistor values?▼

Common resistor values follow the E12 series: 10, 12, 15, 18, 22, 27, 33, 39, 47, 56, 68, 82, and their multiples (×10, ×100, ×1k, etc.). The most frequently used values include 100Ω, 220Ω, 330Ω, 470Ω, 1kΩ, 4.7kΩ, 10kΩ, and 100kΩ.

Related Tools

Pantone to Hex

Search any Pantone color → get its closest Hex code with live color preview. Cov...

Hex to RGB Converter

Convert HEX color codes to RGB values and vice versa. See a live color preview, ...

Pantone Color Converter

Convert HEX, RGB, or CMYK colors to the closest Pantone match instantly. Find Pa...