Color Code of Resistor

Resistor bands encode numbers. The first two bands are digits, the third is the multiplier, and the tolerance band gives allowed variation.

Concept illustration. Check the component datasheet before wiring.

Try it yourself

Change an input.
See what follows.

A simplified learning model. Values describe the model, not a connected robot.

First bandSecond bandMultiplier band (10 to this power)

Resistor bands encode numbers. The first two bands are digits, the third is the multiplier, and the tolerance band gives allowed variation.

Concept illustration; component appearance and scale are simplified.

Key idea

A 4-band resistor uses first digit, second digit, multiplier, and tolerance. Gold tolerance is commonly +/-5%.

Use in robot

Color codes help identify LED resistors, pull-up/pull-down resistors, and voltage-divider values.

Safe wiring

Always remove power before measuring resistance with a multimeter.

Classroom check

Decode a resistor by color, then verify it with a multimeter and compare the tolerance range.

Compare current controllers and sensing options before adapting a Nano circuit. Match voltage, interfaces, and timing.

Explore real robotics applications, from mobile robots to inspection and joint motion. Define a measurable target and test one change at a time.