SMD Resistor Code Calculator

The marking identifies a nominal resistance, not measured tolerance, temperature behavior or safe power handling. Verify the part datasheet for design decisions.

Resistor marking

Format

—Enter a code such as 472, 4991, 4R7, or 68X.

—Normalized marking

—Detected format

Resistance → marking reverse lookup

Enter a resistance to find a practical 3-digit, 4-digit, and nearest EIA-96 marking candidate.

ResistanceUnit

—3-digit / R candidate

—4-digit candidate

—Nearest EIA-96

—EIA-96 relative error

Ready.

Printed code is not a full specification

Numeric and EIA-96 markings identify nominal resistance. Package power rating, tolerance, temperature coefficient and pulse limits require the actual part datasheet.

EIA-96 is a lookup code

The first two digits select one of 96 E96 values and the final letter supplies a multiplier; it is not read like a normal three-digit marking.

Governing electrical relation

3/4-digit or EIA-96 code → nominal resistance — component-marking decoder.

How to cross-check the result

For 3/4-digit codes, split significant digits and multiplier. For EIA-96, verify the lookup value and letter multiplier independently.

Real-component boundary

Package power, TCR and tolerance require the actual part specification. Component tolerance, temperature, parasitics, datasheet limits, installation rules, and hazardous-energy safety are not inferred by this idealized calculator.