1. What is a Three Band Resistor Calculator?

Definition: This calculator determines the resistance value of a three-band resistor based on its color code.

Purpose: It helps electronics hobbyists, engineers, and students quickly decode resistor values without manual calculation.

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 (third color band)

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

3. Importance of Resistor Color Codes

Details: Color coding is a standardized way to represent resistor values and tolerances, essential for proper circuit design and troubleshooting.

4. Using the Calculator

Tips: Select the color of each band from the dropdown menus. The first two bands are digits (0-9), and the third band is the multiplier.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between 3, 4, and 5 band resistors?
A: 3-band resistors have 2 digits and a multiplier. 4-band adds a tolerance band, and 5-band has 3 digits plus multiplier and tolerance.

Q2: How do I read resistor bands?
A: Start from the band closest to the end. The tolerance band (if present) is usually gold or silver and spaced farther apart.

Q3: What if my resistor has more than 3 bands?
A: Use our 4-band or 5-band resistor calculators for more precise resistors with tolerance information.

Q4: Why are some resistance values not standard?
A: Resistors follow the E-series of preferred values (E6, E12, E24, etc.) to cover a logarithmic range of values.

Q5: How accurate are 3-band resistors?
A: Without a tolerance band, 3-band resistors typically have ±20% tolerance. For more precision, use resistors with more bands.