SMD Resistor Code Calculator — 3-digit, 4-digit and EIA-96
Decode 3-digit, 4-digit and EIA-96 surface-mount resistor markings, including R-notation and underlined codes.
Example: SMD code 103 is 10 kΩ (3-digit).
Formula
3-digit: AB × 10^C 4-digit: ABC × 10^D EIA-96: E96[code] × letterCalculations follow IEC 60062 / EIA-96.
Worked example
SMD code 103 is 10 kΩ (3-digit).
3-digit decoding
First two digits are 10; the third is the power of ten, so 10 × 10^3.
R = 10 kΩ
Frequently asked questions
What does 103 mean on an SMD resistor?
10 kΩ. The first two digits are the significant figures (10) and the third is the number of zeros to add, so 103 is 10 followed by three zeros — 10,000 Ω. Three-digit markings are normally 5% parts.
Why do some SMD resistors have a letter in the code?
That is EIA-96, used on 1% parts. Two digits index a position in the 96-value E96 series and the letter gives a power-of-ten multiplier — so 01C is the first E96 value (100 Ω) times 100, or 10 kΩ. It exists because three digits cannot express E96 values.
What does the R mean in 4R7?
R stands in for the decimal point, because a printed dot would be lost at that size. 4R7 is 4.7 Ω and R047 is 0.047 Ω. You will see the same convention on capacitors and inductors.
What is a resistor marked 000 or 0?
A zero-ohm link — a wire in a resistor package, so a board can be jumpered by the same machine that places the resistors. It still has a current rating, usually 1–2 A.
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