Select Code Type
Examples: 104, 472, 4R7, 104K, 2R2, A3
Capacitance Result
Common Capacitor Codes
How Capacitor Codes Work
Common capacitor markings use numeric or alphanumeric codes to represent capacitance. The most common systems include 3-digit EIA, 4-digit EIA, R-code markings and EIA-198 codes.
3-Digit EIA Code
The first two digits represent significant figures. The third digit represents the number of zeros to add. The resulting capacitance is expressed in picofarads.
104 → 100,000 pF4-Digit EIA Code
The first three digits represent significant figures. The fourth digit represents the multiplier.
1042 → 10,400 pFR-Code
The letter R is used to represent the decimal point, which is especially useful for capacitance values below 10 pF.
4R7 → 4.7 pFEIA-198 Code
EIA-198 uses a letter and a number to identify standard capacitance values and their multiplier.
A3 → 1,000 pFCommon Capacitor Code Examples
The following examples illustrate commonly encountered capacitance marking formats.
| Code | Code Type | Capacitance | Equivalent |
|---|---|---|---|
101
|
3-Digit EIA | 100 pF | 0.1 nF |
102
|
3-Digit EIA | 1,000 pF | 1 nF |
103
|
3-Digit EIA | 10,000 pF | 10 nF |
104
|
3-Digit EIA | 100,000 pF | 100 nF / 0.1 µF |
221
|
3-Digit EIA | 220 pF | 0.22 nF |
472
|
3-Digit EIA | 4,700 pF | 4.7 nF |
4R7
|
R-Code | 4.7 pF | 0.0047 nF |
2R2
|
R-Code | 2.2 pF | 0.0022 nF |
104K
|
3-Digit + Tolerance | 100,000 pF | 100 nF ±10% |
A3
|
EIA-198 | 1,000 pF | 1 nF |
Understanding Capacitor Markings
What Does 104 Mean on a Capacitor?
A common 3-digit capacitor code such as 104 represents a capacitance value in picofarads. The first two digits are the significant figures and the third digit indicates the number of zeros.
Therefore: 104 = 10 × 10⁴ pF = 100,000 pF which is equal to: 100 nF = 0.1 µF
What Does R Mean in a Capacitor Code?
In many capacitor marking systems, the letter R is used as a decimal point. For example:
- 4R7 = 4.7 pF
- 2R2 = 2.2 pF
- 0R5 = 0.5 pF
What Does the Last Letter Mean?
A letter following the capacitance code may indicate capacitance tolerance. Common tolerance codes include:
- F = ±1%
- G = ±2%
- J = ±5%
- K = ±10%
- M = ±20%
- Z = -20%+80%
Does a Capacitor Code Show Voltage?
Not necessarily. A capacitance marking such as 104 primarily identifies the capacitance value. Rated voltage, dielectric type, temperature characteristics, tolerance and other specifications may use separate markings or may only be defined by the manufacturer's part number or datasheet.