SMD Resistor Code Calculator
Decode 3-digit, 4-digit and EIA-96 SMD resistor markings to ohms — with the R-decimal style and tolerance handled.
SMD Resistor Code Calculator computes the resistance behind 3-digit, 4-digit and EIA-96 chip resistor markings — free, instant and private in your browser. Rework techs and engineers identifying parts on assembled boards use it to skip the datasheet algebra: type your numbers, read the answer with the substituted formula shown step by step, and share an exact permalink of the calculation.
About SMD Resistor Code Calculator
SMD Resistor Code Calculator computes the resistance behind 3-digit, 4-digit and EIA-96 chip resistor markings using the standard engineering relation: 3/4-digit: digits × 10^(last digit); EIA-96: 2-digit lookup × letter multiplier; R marks the decimal point. Worked live: '473' is 47 × 10³ = 47 kΩ; '01C' in EIA-96 is 100 × 100 = 10 kΩ. The result recalculates on every keystroke, the worked-example panel shows your numbers substituted into the formula, and the Copy permalink button encodes the inputs in the URL so a colleague opens exactly your calculation. Everything runs client-side — nothing you type leaves your device.
How to use SMD Resistor Code Calculator
- 1Enter your values — the tool starts with realistic defaults for this exact use case, so the worked example is meaningful immediately.
- 2Read the live result and the worked-example panel, which substitutes your numbers into the formula step by step.
- 3Adjust any input to compare scenarios, then use Copy result or Copy permalink to share the calculation.
Why use SMD Resistor Code Calculator?
- ✓Implements the real formula — 3/4-digit: digits × 10^(last digit) — with the substitution shown, not a black box
- ✓Built for rework techs and engineers identifying parts on assembled boards
- ✓Copy result and permalink buttons — share the exact calculation in a README, forum answer or design review
- ✓100% free, no sign-up, runs entirely in your browser (works offline once loaded)
Frequently asked questions
How do you calculate smd resistor code?+
The resistance behind 3-digit, 4-digit and EIA-96 chip resistor markings follows 3/4-digit: digits × 10^(last digit); EIA-96: 2-digit lookup × letter multiplier; R marks the decimal point. For example, '473' is 47 × 10³ = 47 kΩ; '01C' in EIA-96 is 100 × 100 = 10 kΩ. The calculator applies the same relation and shows the substituted arithmetic so you can verify every step.
What does the letter in a code like 01C mean?+
That's EIA-96 (±1 % parts): the two digits index a 96-value table of significant figures and the letter sets the multiplier (A=1, B=10, C=100 …). It packs three significant figures onto a tiny 0603 — but you need the table, which this tool embeds.
My chip resistor has no marking at all — now what?+
0402 and smaller are routinely unmarked. Measure in-circuit with the board unpowered (watch for parallel paths), lift one end for a clean reading, or pull the value from the design's BOM/position files if you have them.
Is the SMD Resistor Code Calculator free and private?+
Yes — completely free with no sign-up or usage limits, and it runs entirely in your browser: the values you enter are never uploaded or stored on a server.
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