IP331.com | Online Tools
HomeElectronics & PhysicsResistor Color Code Calculator

Resistor Color Code Calculator

Decode 4-Band and 5-Band Resistor Color Codes

Select Band Count
Select Band Colors
Band 1
Band 2
Multiplier
Tolerance

Resistor Color Code Chart

Black=0, Brown=1, Red=2, Orange=3, Yellow=4
Green=5, Blue=6, Violet=7, Gray=8, White=9
Gold=±5% (tolerance) / ×0.1 (multiplier)
Silver=±10% (tolerance) / ×0.01 (multiplier)
No band = ±20% tolerance

The resistor color code system uses colored bands to indicate resistance value, multiplier, and tolerance. Memorize the sequence with the mnemonic "BBROYGBVGW" for the rainbow color order.

Read the bands from the end closest to the edge. For 4-band: first two are digits. For 5-band: first three are digits. The last band(s) indicate tolerance.

How to Read Resistor Color Codes

The resistor color code is a standardized marking system. Each color represents a number 0-9. The first bands are significant digits, the next is the multiplier (power of ten), and the final band is tolerance. Position the resistor so the tolerance band (gold/silver) is on the right, then read left to right.

4-Band System

2 digits + multiplier + tolerance. Example: Brown-Black-Red-Gold = 1 0 ×100 = 1kΩ ±5%.

5-Band System

3 digits + multiplier + tolerance. Used for precision (±1% or better). Example: Brown-Black-Black-Brown-Brown = 1kΩ ±1%.

Multiplier

The multiplier band indicates 10^n. Red = ×100, Orange = ×1k, Yellow = ×10k, Gold = ×0.1, Silver = ×0.01.

Tolerance

Brown=±1%, Red=±2%, Gold=±5%, Silver=±10%. Lower tolerance = higher precision = higher cost.

Teaching Example: Resistor with bands: Brown(1) - Black(0) - Red(×100) - Gold(±5%).
Digits: 1 and 0 = 10. Multiplier: ×100 = 10 × 100 = 1000Ω = 1kΩ. Tolerance: ±5%. Range: 950Ω to 1050Ω.

Applications

Circuit Design Repair Hobby Electronics Testing Education

Frequently Asked Questions

How to read a 4-band resistor?
First 2 bands are digits, 3rd is multiplier, 4th is tolerance. Example: Brown-Black-Red-Gold = 1 0 ×100 = 1000Ω = 1kΩ ±5%.
What is the resistor color mnemonic?
"BBROY Great Britain Very Good Wife" = Black Brown Red Orange Yellow Green Blue Violet Gray White. Or simply: BBROYGBVGW.
Which end to read first?
Position the resistor so the tolerance band (gold or silver) is on the right. Read left to right. The first band is closest to the edge.
When to use 5-band resistors?
5-band resistors provide 3 significant digits for precision (±1% or better). Use in measurement circuits, voltage references, and precision analog circuits.

More Electronics Tools

Free online calculators and tools covering mathematics, unit conversion, text processing, and daily life. Accurate, fast, mobile-friendly, and completely free to use.

© 2026 IP331.com — Free Online Tools. All rights reserved.

About · Contact · Privacy Policy · Cookie Policy · Terms of Use · Disclaimer · Sitemap