Capacitor Code Calculator
Decode 3-digit ceramic and film capacitor codes to pF, nF and µF in one step. Includes a pF ↔ nF ↔ µF unit converter for when you have the value but need a different unit.
Last updated: May 2026
Enter a 3-digit capacitor code to decode it.
Formula: pF = (d1×10 + d2) × 10d3
How the 3-digit capacitor code works
Ceramic and film capacitors too small to print the full value use a 3-digit code. The first two digits are the significant figures. The third digit is the multiplier exponent — the number of zeros to append. The result is always in picofarads (pF).
Examples: 104 = 10 × 104 pF = 100,000 pF = 100 nF = 0.1 µF. 472 = 47 × 102 pF = 4,700 pF = 4.7 nF. 221 = 22 × 101 pF = 220 pF.
Special third-digit codes: 8 means ×0.01, 9 means ×0.1 — used for sub-100 pF values in some manufacturers' coding. Codes under 100 (e.g. "47" with no third digit) are read as direct pF values.
Common capacitor value reference
| Code | pF | nF | µF | Typical use |
|---|---|---|---|---|
| 100 | 10 pF | 0.01 nF | — | RF tuning, small bypass |
| 101 | 100 pF | 0.1 nF | — | HF bypass, filter |
| 102 | 1,000 pF | 1 nF | 0.001 µF | High-frequency decoupling |
| 103 | 10,000 pF | 10 nF | 0.01 µF | Snubber, coupling |
| 104 | 100,000 pF | 100 nF | 0.1 µF | Bypass / decoupling (most common) |
| 105 | 1,000,000 pF | 1,000 nF | 1 µF | Power supply filter |
| 472 | 4,700 pF | 4.7 nF | 0.0047 µF | Audio coupling, timing |
| 226 | 22,000,000 pF | 22,000 nF | 22 µF | Bulk filter (electrolytic equiv.) |
Frequently Asked Questions
What does the letter after the code mean (e.g. 104K, 104M)?
The letter is the tolerance code. K = ±10%, M = ±20%, J = ±5%, F = ±1%, G = ±2%. So "104K" is 100 nF ±10%. You may also see a voltage rating suffix (e.g. 104K50 = 100 nF, ±10%, 50 V). Ignore the letters when decoding the capacitance value — only the three digits matter.
Why is the 0.1 µF capacitor so common on PCBs?
A 100 nF (0.1 µF) ceramic capacitor placed close to each IC power pin suppresses high-frequency noise that travels along the supply rail. Digital chips switch millions of times per second; each switch draws a brief current spike. A local ceramic cap delivers that charge instantly, before the noise can reach other parts of the board. It is the single most commonly used passive component in digital design.
How do I convert between pF, nF and µF mentally?
Each step is a factor of 1,000: pF × 1,000 = nF is wrong — divide by 1,000. 1,000 pF ÷ 1,000 = 1 nF. 1,000 nF ÷ 1,000 = 1 µF. Going up: 1 µF × 1,000 = 1,000 nF = 1,000,000 pF. A quick shortcut: if the pF value has 6 zeros (1,000,000 pF), it is 1 µF. If it has 3 zeros (1,000 pF), it is 1 nF.
Can I use a ceramic 104 capacitor instead of an electrolytic?
For bypass and decoupling, yes — ceramic capacitors are preferred because they have lower ESR (equivalent series resistance) and no polarity. For bulk energy storage in power supplies (100 µF+), you still need electrolytic or tantalum capacitors because ceramics in those values are large and expensive. Many modern designs use a combination: one large electrolytic for bulk filtering and one 100 nF ceramic per IC for high-frequency bypass.