1. What is a Colour Code Resistor Calculator?

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

Purpose: It helps electronics enthusiasts and engineers quickly decode 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, 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 on small components where printing numbers would be impractical.

4. Using the Calculator

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

5. Frequently Asked Questions (FAQ)

Q1: What if my resistor has 4 or 5 bands?
A: This calculator handles 3-band resistors. For 4-band resistors, the first three bands work the same way (two digits and multiplier), and the fourth band indicates tolerance.

Q2: What do gold and silver mean in the multiplier band?
A: Gold represents ×0.1 (10^-1) and silver represents ×0.01 (10^-2), used for very small resistance values.

Q3: How accurate are resistor color codes?
A: The color code gives the nominal value. Actual resistance depends on the tolerance band (not included in this 3-band calculator).

Q4: Why do some resistors start with black band?
A: Black as first digit means 0, which would make the value start with 0 (like 02 = 2). This is uncommon but valid.

Q5: What's the highest value this calculator can show?
A: With white (9) in all bands: 99 × 10^9 = 99 GΩ (gigaohms).