Capacitor Code Calculator (104, 223, 4R7)

Type the code printed on a ceramic or film capacitor to get its capacitance in pF, nF and µF.

Capacitance
Picofarads
Nanofarads
Microfarads
Tolerance

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How it works

Small capacitors are marked with a three-digit code in picofarads: the first two digits are the value and the third is the number of zeros to add. An R marks the decimal point for values under 10 pF.

A letter after the code gives the tolerance, for example J = ±5%, K = ±10% and M = ±20%.

C (pF) = first two digits × 10^(third digit)

Worked example

A capacitor marked 104K is 10 followed by 4 zeros: 100,000 pF = 100 nF = 0.1 µF, with ±10% tolerance. That's the classic decoupling capacitor next to almost every chip.

Frequently asked questions

What does 104 mean on a capacitor?

104 means 10 × 10⁴ pF = 100,000 pF, which is 100 nF or 0.1 µF.

Is the voltage rating included in the code?

Not in the three-digit code. Some capacitors print the voltage separately (for example 50V or 2A for 100 V on film capacitors). Check the datasheet when in doubt.

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