Question 1

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

Accepted Answer

Read from left to right: Band 1 (first digit), Band 2 (second digit), Band 3 (multiplier/number of zeros), Band 4 (tolerance). For example: Brown-Black-Red-Gold = 1-0-×100-±5% = 1000Ω or 1kΩ ±5%.

Question 2

What does the gold or silver band mean?

Accepted Answer

Gold and silver bands indicate tolerance. Gold = ±5%, Silver = ±10%. These are the most common tolerance bands on standard resistors. No band typically means ±20% tolerance.

Question 3

Which end do I start reading from?

Accepted Answer

The tolerance band (gold, silver, or sometimes red/brown) is usually closest to one end. Start reading from the opposite end. If unsure, try both directions and see which gives a standard value (like 1kΩ, 10kΩ, etc.).

Question 4

What are E12 and E24 series resistors?

Accepted Answer

E12 and E24 are standard resistor value series. E12 has 12 values per decade (10% tolerance), E24 has 24 values per decade (5% tolerance). This ensures consistent, manufacturable values like 1Ω, 1.2Ω, 1.5Ω, 1.8Ω, 2.2Ω, etc.

Question 5

Can 5 or 6 band resistors be calculated?

Accepted Answer

This calculator handles standard 4-band resistors. 5-band resistors add a third significant digit for higher precision (1% tolerance). 6-band resistors include a temperature coefficient. The reading principle is similar but with additional bands.

Resistor Color Code Calculator

Resistor Calculator

Resistance Value

Resistor Color Code Reference

Color Values:

Multiplier Colors:

Tolerance Colors:

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