Capacitor Code Calculator
Turn the three-digit code printed on a ceramic capacitor into picofarads, nanofarads and microfarads, with the tolerance letter decoded too.
How to use it
- Type the code exactly as printed, for example 104 or 104K.
- The first two digits are the value and the third is the number of zeros to add, in picofarads.
- A trailing letter is the tolerance — K is ± 10%, J is ± 5%.
Examples
| 104 | 100 nF (0.1 µF) |
| 223K | 22 nF ± 10% |
Small ceramic capacitors are too tiny to print a value like "100nF" on, so they carry a three-digit code instead, the same system used for resistors' numeric equivalents. The first two digits are significant figures and the third is a power-of-ten multiplier, always in picofarads — the base unit the whole system is built around.
This tool decodes any code you type, converts the result into picofarads, nanofarads and microfarads at once, and reads the tolerance letter if one follows the digits.
How the digits work
Take 104: the first two digits, 1 and 0, give 10. The third digit, 4, means "add four zeros." So 10 followed by four zeros is 100,000 pF. Converted, that is 100 nF, or 0.1 µF — three ways of writing the identical value, which is exactly why the conversion table matters more than the raw code.
Common codes and their values
| Code | Picofarads | Microfarads | Common name |
|---|---|---|---|
| 100 | 10 pF | 0.00001 µF | 10pF |
| 101 | 100 pF | 0.0001 µF | 100pF |
| 102 | 1,000 pF | 0.001 µF | 1nF |
| 103 | 10,000 pF | 0.01 µF | 10nF |
| 104 | 100,000 pF | 0.1 µF | 100nF — the most common decoupling cap |
| 105 | 1,000,000 pF | 1 µF | 1µF |
| 224 | 220,000 pF | 0.22 µF | 220nF |
The tolerance letter
- F — ±1%
- G — ±2%
- J — ±5%, the most common on general-purpose ceramics
- K — ±10%, common on cheaper bulk capacitors
- M — ±20%
When there is no code at all
Larger capacitors — electrolytics, tantalums, film types — usually have enough body surface to print the value and voltage rating directly, such as "470µF 25V", so the digit-code system is really only needed for capacitors too small to print on legibly. If a part shows a plain value like that, you already have the answer and do not need this decoder.
Questions people ask
Why is 104 equal to 0.1 µF and not 104 pF?
Because the third digit is a multiplier, not a value. 10 followed by four zeros is 100 000 pF, which is 100 nF or 0.1 µF.
What about capacitors with the value printed in full?
Larger electrolytics usually print the value and voltage directly, such as 470 µF 25 V. The code system is mainly for small ceramics with no room for it.
Does this page work offline?
Yes, after the first visit. The service worker caches it, so the reference stays available with no connection.
Last updated 22 August 2026