What do resistor color bands mean?

Each color represents a digit (0-9). In a 4-band resistor: band 1 = first digit, band 2 = second digit, band 3 = multiplier (power of 10), band 4 = tolerance. In 5-band: bands 1-3 are digits, band 4 is multiplier, band 5 is tolerance.

What is the resistor color code?

Black=0, Brown=1, Red=2, Orange=3, Yellow=4, Green=5, Blue=6, Violet=7, Gray=8, White=9. Multipliers: Black=1, Brown=10, Red=100, Orange=1k, Yellow=10k, Green=100k, Blue=1M. Tolerance: Gold=5%, Silver=10%, Brown=1%.

How do I read a red-red-brown-gold resistor?

Red=2, Red=2, Brown=multiplier 10, Gold=5% tolerance. Value = 22 times 10 = 220 ohms plus or minus 5%. This is a common resistor value used in LED circuits.

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

5-band resistors have three significant digit bands instead of two, allowing more precise values. A 4-band 220-ohm resistor has 2% precision from the value (22 times 10). A 5-band can specify values like 221 ohms or 220 ohms to higher precision.

Resistor Color Code Calculator — 4 & 5 Band

How this tool fits your workflow

Reading resistor color codes

Resistors are too small to print numerical values on, so color bands represent the resistance value. The color-to-digit mapping uses the mnemonic that most electronics students learn: Black, Brown, Red, Orange, Yellow, Green, Blue, Violet, Gray, White = 0 through 9. The multiplier band shifts the decimal point (Brown = multiply by 10, Red = by 100, etc.).

Tolerance is typically gold (5%) or silver (10%) on 4-band resistors, and brown (1%), red (2%), or green (0.5%) on precision 5-band resistors. The tolerance tells you how much the actual resistance can deviate from the marked value.

Standard resistor values (E-series)

Resistors are manufactured in standard value series: E12 (12 values per decade, 10% tolerance), E24 (24 values, 5% tolerance), E48 (48 values, 2%), E96 (96 values, 1%), E192 (192 values, 0.5%). These series are spaced so every value is within tolerance of a standard value — you never need a non-standard resistor.

Common values include 100, 220, 330, 470, 680, 1000 ohms (E12 series). If you need 250 ohms, you would use a 220 or 270 ohm resistor depending on whether you need a value above or below. For precision work, use E96 series 1% resistors where nearly any value is available as a standard part.

Frequently asked questions

What do resistor color bands mean?: Each color represents a digit (0-9). In a 4-band resistor: band 1 = first digit, band 2 = second digit, band 3 = multiplier (power of 10), band 4 = tolerance. In 5-band: bands 1-3 are digits, band 4 is multiplier, band 5 is tolerance.
What is the resistor color code?: Black=0, Brown=1, Red=2, Orange=3, Yellow=4, Green=5, Blue=6, Violet=7, Gray=8, White=9. Multipliers: Black=1, Brown=10, Red=100, Orange=1k, Yellow=10k, Green=100k, Blue=1M. Tolerance: Gold=5%, Silver=10%, Brown=1%.
How do I read a red-red-brown-gold resistor?: Red=2, Red=2, Brown=multiplier 10, Gold=5% tolerance. Value = 22 times 10 = 220 ohms plus or minus 5%. This is a common resistor value used in LED circuits.
What is the difference between 4-band and 5-band resistors?: 5-band resistors have three significant digit bands instead of two, allowing more precise values. A 4-band 220-ohm resistor has 2% precision from the value (22 times 10). A 5-band can specify values like 221 ohms or 220 ohms to higher precision.