# Resistor calculator

A resistor is an electronic component that limits the flow of current in a circuit. Here’s a simple calculator to help you calculate the resistance of a resistor:

1. Determine the color bands on your resistor. Typically, resistors have four or five color bands that indicate the value of the resistance.
2. Find the tolerance of the resistor. The tolerance is indicated by a colored band that is separate from the other bands. The tolerance band indicates the range of values that the actual resistance of the resistor may fall within.
3. Use the color codes to determine the resistance value of the resistor. Each color band corresponds to a digit. The first two bands represent the first two digits of the resistance value, the third band represents a multiplier that determines the number of zeros to add to the first two digits, and the fourth band (if present) indicates the tolerance.

Here’s a table of the color codes:

Color Code 1st Band 2nd Band Multiplier Tolerance
Black 0 0 1
Brown 1 1 10 ±1%
Red 2 2 100 ±2%
Orange 3 3 1,000
Yellow 4 4 10,000
Green 5 5 100,000 ±0.5%
Blue 6 6 1,000,000 ±0.25%
Violet 7 7 10,000,000 ±0.1%
Gray 8 8 100,000,000 ±0.05%
White 9 9 1,000,000,000
Gold 0.1 ±5%
Silver 0.01 ±10%
1. Calculate the resistance value. Once you know the digit values of the color bands, you can use the following formula to calculate the resistance value:

Resistance = (1st digit × 10 + 2nd digit) × multiplier

For example, if a resistor has the color bands brown-black-red-gold, the resistance value would be:

Resistance = (1 × 10 + 1) × 100 = 110 Ω with a tolerance of ±1%.

I hope that helps you! Let me know if you have any further questions.