Capacitor Code Calculator
Decode ceramic capacitor 3-digit codes or convert a value to its code.
Component Values
Enter 3-digit code (e.g. 104, 472K, 103M)
Results
3-digit EIA capacitor marking
Common Capacitor Values — Click to Decode
| Code | pF | nF | µF |
|---|---|---|---|
| 100 | 10 pF | 0.010 nF | 0.000010 µF |
| 220 | 22 pF | 0.022 nF | 0.000022 µF |
| 101 | 100 pF | 0.10 nF | 0.00010 µF |
| 471 | 470 pF | 0.47 nF | 0.00047 µF |
| 102 | 1000 pF | 1.0 nF | 0.0010 µF |
| 472 | 4700 pF | 4.7 nF | 0.0047 µF |
| 103 | 10000 pF | 10 nF | 0.010 µF |
| 473 | 47000 pF | 47 nF | 0.047 µF |
| 104 | 100000 pF | 1.0e+2 nF | 0.10 µF |
| 474 | 470000 pF | 4.7e+2 nF | 0.47 µF |
| 105 | 1000000 pF | 1.0e+3 nF | 1.0 µF |
Click any row to decode that code. 3rd digit is the power-of-10 multiplier (in pF). Exception: 8 = ×0.01, 9 = ×0.1.
Tolerance Letter Codes
| Letter | Tolerance | Typical Type |
|---|---|---|
| J | ±5% | Film |
| K | ±10% | Ceramic |
| M | ±20% | Ceramic/Electrolytic |
| F | ±1% | Film/NPO |
| G | ±2% | — |
| Z | +80%/−20% | — |
How to Read Capacitor Codes
Ceramic capacitors use a 3-digit code: the first two digits are the significant figures, the third is the power-of-10 multiplier in picofarads. Example: 104 → 10 × 10⁴ pF = 100,000 pF = 100 nF = 0.1 µF. The most common value in electronics.
Special cases: if the third digit is 8, multiply by 0.01 (so 158 = 15 × 0.01 = 0.15 pF). If 9, multiply by 0.1 (159 = 15 × 0.1 = 1.5 pF). Letters after the code indicate tolerance (J=±5%, K=±10%, M=±20%) and sometimes voltage rating.
Electrolytic capacitors show their value directly (e.g., "100µF 25V"). Film capacitors may use codes or direct values. SMD capacitors (0402, 0603) are often unmarked, so you need to know the reel label value.
3-digit code formula
Value (pF) = [D1 D2] × 10^D3Example: 104 = 10 × 10⁴ = 100,000 pF = 100 nFKey Points
- Code = [D1 D2] × 10^D3 pF
- 104 = 100 nF = 0.1 µF (most common bypass cap)
- 103 = 10 nF, 102 = 1 nF, 101 = 100 pF
- Tolerance: J=±5%, K=±10%, M=±20%
- Exception: 3rd digit 8 = ×0.01, 9 = ×0.1
- Electrolytic caps show value directly (100µF 25V)
Applications
- Identifying unlabeled capacitors from PCBs
- Selecting correct bypass capacitor (100nF = 104)
- Reading capacitor values when ordering replacements
- Understanding ceramic capacitor markings in schematics
- Decoding vintage or salvaged components
FAQ
What does 104 mean on a capacitor?
104 = 10 × 10⁴ pF = 100,000 pF = 100 nF = 0.1 µF. This is the most common ceramic capacitor value, widely used for decoupling near IC power pins.
How to read capacitor codes?
The 3-digit code: first two digits = significant figures, third = power of 10 exponent in pF. Value = [D1 D2] × 10^D3 pF. Letters after the code indicate tolerance.
What is 100nF in capacitor code?
100 nF = 100,000 pF → code 104. The digits "10" × 10⁴ = 100,000 pF = 100 nF. Also written as 0.1 µF.
What does the letter after the capacitor code mean?
Tolerance: J=±5%, K=±10%, M=±20%, F=±1%, G=±2%. A two-character code like "2A" indicates voltage rating (2A = 100V).
How to decode SMD capacitor markings?
Small SMD ceramics (0402, 0603) are often unmarked. Large SMD ceramics may use a 3-digit code. If unmarked, check the reel or tape label. Electrolytic SMD caps show value directly.
What is the difference between 104 and 105 capacitors?
104 = 100 nF (0.1 µF), 105 = 1,000 nF (1 µF). One decade difference. 104 is the standard bypass cap; 105 is used for bulk decoupling.
Did you know? The 3-digit capacitor code system (e.g. "104" = 100 nF) was inherited from ceramic capacitor marking conventions developed in the 1960s. The code mirrors the EIA resistor color code: first two digits are significant figures, third is the multiplier (number of zeros in pF).