1. What is a 4-Band Resistor Color Code Calculator?

Definition: This calculator determines the resistance value and tolerance of a 4-band resistor based on its color code.

Purpose: It helps electronics engineers, technicians, and hobbyists quickly identify 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 (1st band color)
• \( band2 \) — Second significant digit (2nd band color)
• \( band3 \) — Multiplier/exponent (3rd band color)
• 4th band indicates tolerance percentage

Explanation: The first two bands represent digits, the third is the power-of-ten multiplier, and the fourth indicates tolerance.

3. Importance of Resistor Color Codes

Details: Color coding allows quick identification of resistor values and tolerances, essential for circuit design, troubleshooting, and repair.

4. Using the Calculator

Tips: Select the color of each band from the dropdown menus. The calculator will display the resistance value and tolerance range.

5. Frequently Asked Questions (FAQ)

Q1: What if my resistor has 5 or 6 bands?
A: This calculator is for 4-band resistors only. 5-band resistors have an additional significant digit, and 6-band resistors add a temperature coefficient.

Q2: How do I read the resistor bands?
A: Hold the resistor with the tolerance band (usually gold or silver) to the right. Read colors left to right.

Q3: What does tolerance mean?
A: Tolerance indicates how much the actual resistance may vary from the marked value (e.g., ±5%).

Q4: Why are some multiplier values negative?
A: Gold (10^-1) and Silver (10^-2) are used for very small resistance values (fractions of an ohm).

Q5: What's the most common tolerance?
A: Gold (±5%) is most common in general-purpose resistors, while precision resistors often use brown (±1%) or better.