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Resistor Color Code Calculator

Decode resistor color bands to value or find the right colors for any resistance โ€” supports 4-band and 5-band resistors

Bands:
Mode:

Results

Select band colors to see the resistance value

About This Tool

Every through-hole resistor has colored bands that encode its resistance value and tolerance. Reading these bands by memory works for common values, but gets tricky with 5-band precision resistors or uncommon multipliers. This calculator decodes any combination of color bands instantly. Use Color โ†’ Value mode to select band colors and see the resistance, or switch to Value โ†’ Color mode to type a resistance and get the matching color code. The interactive resistor graphic updates in real time so you can visually verify the bands before soldering. Supports both 4-band resistors (2 digits + multiplier + tolerance) and 5-band precision resistors (3 digits + multiplier + tolerance). Shows the full tolerance range so you know the minimum and maximum resistance to expect from the component.

How to Use

1. Choose 4-band or 5-band to match your resistor 2. In Color โ†’ Value mode: click color swatches for each band to decode the resistance 3. In Value โ†’ Color mode: type a resistance value and select tolerance to find the band colors 4. Read the result: resistance value, tolerance percentage, and min/max range 5. The resistor diagram updates in real time to show your selected bands 6. Use "Copy Link" to save or share the result

Formula

4-band: Value = (Band1 ร— 10 + Band2) ร— Multiplier ยฑ Tolerance% 5-band: Value = (Band1 ร— 100 + Band2 ร— 10 + Band3) ร— Multiplier ยฑ Tolerance%

Frequently Asked Questions

How do I read resistor color codes?
Hold the resistor so the grouped bands are on the left. Read left to right: the first 2 bands (4-band) or 3 bands (5-band) are digits, the next band is the multiplier (number of zeros), and the last band (separated by a gap) is the tolerance. For example, Brown-Black-Red-Gold = 10 ร— 100 = 1,000 ฮฉ (1 kฮฉ) ยฑ5%.
What is the difference between 4-band and 5-band resistors?
4-band resistors have 2 significant digits (e.g., 47 ร— multiplier), giving values like 4.7 kฮฉ or 47 kฮฉ. 5-band resistors have 3 significant digits (e.g., 470 ร— multiplier), allowing more precise values like 4.70 kฮฉ or 47.5 kฮฉ. 5-band resistors are used in precision circuits and typically have tighter tolerances (1% or better).
What color is a 10k resistor?
A 10 kฮฉ resistor in 4-band is Brown (1), Black (0), Orange (ร—1,000), Gold (ยฑ5%). In 5-band it's Brown (1), Black (0), Black (0), Red (ร—100), Brown (ยฑ1%). The body of most 10k resistors is beige or light blue depending on the type.
What does the gold band on a resistor mean?
Gold has two meanings depending on its position. As a tolerance band (last band, separated by a gap), gold means ยฑ5% tolerance. As a multiplier band (3rd or 4th band from left), gold means ร—0.1, which is used for sub-1ฮฉ resistor values like 4.7 ฮฉ (Yellow-Violet-Gold).
What is the tolerance band on a resistor?
The tolerance band is the last band on the resistor, usually separated by a wider gap from the other bands. It indicates the manufacturing precision: Gold = ยฑ5%, Silver = ยฑ10%, Brown = ยฑ1%, Red = ยฑ2%. A 1 kฮฉ resistor with ยฑ5% tolerance (gold band) can actually measure anywhere from 950 ฮฉ to 1,050 ฮฉ.
How do I find which end to read from?
The tolerance band (gold, silver, or sometimes brown/red) is always the last band. It's usually separated by a slightly wider gap from the digit bands. The first band is always closer to one end of the resistor. If two ends look similar, gold or silver is almost always the tolerance (last) band โ€” start reading from the opposite end.
What is a 4.7k resistor color code?
4.7 kฮฉ (4,700 ฮฉ) in 4-band is Yellow (4), Violet (7), Red (ร—100), Gold (ยฑ5%). In 5-band it's Yellow (4), Violet (7), Black (0), Brown (ร—10), Brown (ยฑ1%). This is one of the most commonly used resistor values in electronics.