Capacitor Code Decoder

About this tool

Decode the tiny printed marking on a ceramic or film capacitor into an actual capacitance value. Handles the standard 3-digit EIA code (like "104" → 100nF), shorthand notation that uses a unit letter as the decimal point (like "4n7" → 4.7nF), plain 1–2 digit pF values, and a trailing tolerance letter (like the "K" in "473K").

Frequently asked questions

How does the 3-digit code work?

The first two digits are significant figures and the third is a multiplier — the number of zeros to add, in picofarads. So "104" means 10 with 4 zeros: 100,000pF, which is 100nF or 0.1µF.

What does the letter at the end mean?

It's the tolerance code — how far the actual capacitance may vary from the marked value. "K" means ±10%, "J" means ±5%, "M" means ±20%, and so on; it's the capacitor equivalent of a resistor's gold or silver tolerance band.

What's the difference between "4n7" and "104"?

Both describe values in the same ballpark but use different notations — "4n7" is direct shorthand for 4.7nF (the letter stands in for the decimal point), while 3-digit EIA codes like "104" encode the value as two significant digits plus a multiplier exponent instead.