🔋 Capacitor Code Calculator
Enter a ceramic capacitor's printed code (like 104) to get its capacitance in picofarads, nanofarads and microfarads.
Capacitance
100 nF
In picofarads
100,000 pF
nF / µF
100 nF · 0.1 µF
A 3-digit ceramic code is read like the resistor code: the first two digits, then the number of zeros. So 104 = 10 followed by 4 zeros = 100,000 pF = 100 nF. A trailing letter (if present) is the tolerance. 1 µF = 1,000 nF = 1,000,000 pF. 🔒 In your browser.
How the capacitor code calculator works
Small ceramic capacitors are marked with a 3-digit code read like the resistor color code: the first two digits are significant figures and the third is the number of zeros, giving the value in picofarads. So 104 means 10 followed by four zeros = 100,000 pF = 100 nF. The tool decodes it and shows the value in all three common units.
A 1 or 2-digit marking is simply the value in picofarads. A trailing letter (like J or K) is the tolerance, not part of the value. Larger electrolytic capacitors usually print their value and unit directly (e.g. "470 µF"), so they don't need decoding.
Frequently asked questions
How do I read a capacitor code?
The first two digits are the value and the third is the number of zeros, giving picofarads. 104 = 10 with 4 zeros = 100,000 pF = 100 nF; 223 = 22,000 pF = 22 nF.
What does 104 mean on a capacitor?
100 nF (0.1 µF) — the code 104 is 10 × 10⁴ = 100,000 picofarads. It's one of the most common decoupling capacitor values.
What does the letter after the code mean?
It's the tolerance: common ones are J (±5%), K (±10%) and M (±20%). It doesn't change the capacitance value the digits give.
How do I convert pF, nF and µF?
1 µF = 1,000 nF = 1,000,000 pF. So 100 nF = 0.1 µF = 100,000 pF. The tool shows all three units at once.
Do all capacitors use this code?
Mostly small ceramic (and some film) capacitors. Larger electrolytic and tantalum capacitors usually print the capacitance and voltage directly, so there's nothing to decode.