1. What is an SMD Resistor Color Code Calculator?

Definition: This calculator determines the resistance value of SMD resistors based on their 3-digit code.

Purpose: It helps electronics engineers, technicians, and hobbyists quickly decode resistor values for circuit design and repair.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( R \) — Resistance in ohms (Ω)
• \( digit1 \) — First significant digit (0-9)
• \( digit2 \) — Second significant digit (0-9)
• \( multiplier \) — Power of ten multiplier (-2 to 9)

Explanation: The first two digits form the significant figures, which are multiplied by 10 raised to the multiplier value.

3. Importance of Resistor Coding

Details: SMD resistors use numeric codes because their small size makes color bands impractical. Understanding these codes is essential for proper component selection.

4. Using the Calculator

Tips: Enter the first two digits (0-9) and the multiplier (-2 to 9). Common multipliers:

• 0 = ×1Ω
• 1 = ×10Ω
• 2 = ×100Ω
• 3 = ×1kΩ
• -1 = ×0.1Ω
• -2 = ×0.01Ω

5. Frequently Asked Questions (FAQ)

Q1: What does "472" mean on a resistor?
A: 47 × 10² = 4700Ω or 4.7kΩ (First digit=4, second digit=7, multiplier=2)

Q2: How do I read resistors with 4 digits?
A: For 4-digit codes, the first three digits are significant figures (e.g., 1002 = 100 × 10² = 10kΩ)

Q3: What about resistors with letters?
A: Letters indicate specific values or tolerances. "R" means decimal point (e.g., 4R7 = 4.7Ω)

Q4: What's the smallest resistor value this can calculate?
A: With multiplier -2: 0.01Ω (e.g., 00-2 = 0 × 10⁻² = 0.01Ω)

Q5: What's the largest resistor value?
A: With multiplier 9: 99 × 10⁹ = 99 GΩ (though resistors this large are rare)