SMD Resistor Calculator
By John Doe (Electronics Hobbyist) | Last Updated: | Reviewed by: Jane Smith (Electrical Engineer)
Quickly find the resistance value of any SMD resistor by entering its code. This tool supports standard 3-digit, 4-digit, and EIA-96 coding systems. Find more useful tools among the free calculators on CalculatorBolt.
Responsive Ad (e.g., 728x90)
Medium Rectangle Ad (e.g., 300x250)
How It Works
Surface-Mount Device (SMD) resistors use a compact numerical code to indicate their resistance value. This calculator interprets that code based on the system used.
- 3-Digit Code: The first two digits are the significant figures, and the third is a multiplier (power of 10).
- 4-Digit Code: For higher precision resistors, the first three digits are the significant figures, and the fourth is the multiplier.
- EIA-96 Code: A high-precision system where the first two digits correspond to a value from a lookup table, and the letter is a multiplier.
The letter 'R' is used as a decimal point for values under 100 Ω (e.g., `5R6` is 5.6 Ω).
Example Calculations
- Code '103' (3-Digit): 10 × 103 = 10,000 Ω or 10 kΩ.
- Code '4702' (4-Digit): 470 × 102 = 47,000 Ω or 47 kΩ.
- Code '38C' (EIA-96): The code '38' corresponds to 243. The letter 'C' is a multiplier of 100. So, the value is 243 × 100 = 24,300 Ω or 24.3 kΩ.
The letter 'R' acts as a decimal point. So, a code of '2R2' means 2.2 Ω. Similarly, 'R10' would mean 0.10 Ω.
A code of '0', '000', or '0000' indicates a zero-ohm resistor, which is essentially a jumper link used to connect traces on a circuit board. Its resistance is 0 Ω.