1. What is a Resistor Value Calculator from Colors?

Definition: This calculator determines the resistance value of a resistor based on its color bands.

Purpose: It helps electronics engineers, technicians, and hobbyists quickly identify resistor values without memorizing color codes.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( R \) — Resistance value (ohms)
• \( band1 \) — First significant digit (first color band)
• \( band2 \) — Second significant digit (second color band)
• \( band3 \) — Multiplier/exponent (third color band)

Explanation: The first two bands represent digits, while the third band represents the power of ten multiplier.

3. Importance of Resistor Color Codes

Details: Color codes provide a standardized way to represent resistor values on small components where printed numbers would be impractical.

4. Using the Calculator

Tips: Select the colors of each band from the dropdown menus. The calculator will display the resistance value in ohms.

5. Frequently Asked Questions (FAQ)

Q1: What about 4-band or 5-band resistors?
A: This calculator handles 3-band resistors. For 4-band resistors, the fourth band represents tolerance (not included in value calculation).

Q2: What do gold and silver bands mean?
A: When in the multiplier position, gold = ×0.1 (10^-1) and silver = ×0.01 (10^-2).

Q3: How accurate are resistor color codes?
A: The color code gives nominal value. Actual resistance depends on tolerance (shown by additional bands).

Q4: What if my resistor has more bands?
A: 5-band resistors use three digit bands. 6-band resistors may include temperature coefficient.

Q5: Why does the resistance sometimes show in scientific notation?
A: For very large or small values, the calculator may display in scientific format for readability.