Capacitor Code Calculator | 3-Digit Code to Farads
Convert capacitor 3-digit numeric codes (e.g. 104) to actual capacitance values in pF, nF, or µF. Also supports reverse lookup.
How to Use
- To decode: enter the 3-digit code printed on the capacitor (e.g. '104') and click Calculate.
- To encode: enter the capacitance value and select the unit (pF, nF, or µF), then click Calculate.
- The code format is: first two digits are significant figures, third digit is the power of 10 multiplier.
- For example, '104' means 10 × 10⁴ pF = 100,000 pF = 100 nF = 0.1 µF.
- Special codes: '0' to '9' without a third digit indicate the value directly in pF.
- Tolerance and voltage rating are often printed separately as letters (e.g. 'K' = ±10%, 'Z' = +80/-20%).
About Capacitor Codes
The 3-Digit Code System
Small ceramic and film capacitors use a 3-digit marking system similar to resistor color codes. The first two digits are the capacitance value's significant figures, and the third digit is the multiplier (exponent of 10). The base unit is picofarads (pF). So '104' = 10 × 10⁴ pF = 100,000 pF = 0.1µF. This system allows large values to be printed in a very small space.
Special Code Values
Codes '8' and '9' as the third digit have special meanings: '8' means multiply by 0.01, and '9' means multiply by 0.1. So '108' = 10 × 0.01 = 0.1 pF and '109' = 10 × 0.1 = 1 pF. For values below 10pF, the code may be printed directly (e.g., '4R7' means 4.7pF where 'R' represents the decimal point).
Tolerance and Voltage Codes
Additional letters after the 3-digit code indicate tolerance and voltage rating. Common tolerance codes: B=±0.1pF, C=±0.25pF, D=±0.5pF, F=±1%, G=±2%, J=±5%, K=±10%, M=±20%, Z=+80/-20%. Voltage codes vary by manufacturer. Always check the full datasheet when selecting capacitors for precision or high-voltage applications.
Common Capacitor Values and Their Codes
Frequently encountered codes: 101=100pF, 102=1nF, 103=10nF, 104=100nF(0.1µF), 105=1µF, 221=220pF, 472=4.7nF, 473=47nF, 474=470nF. These values correspond to standard E12/E24 series capacitances. The 100nF (0.1µF) bypass capacitor, coded '104', is one of the most common components in electronics, used for power supply decoupling.
Key Features
- Decode 3-digit capacitor codes to pF, nF, and µF simultaneously
- Encode any capacitance value back to the standard code
- Handles special multiplier codes (×0.01 and ×0.1)
- Supports input in pF, nF, or µF units
Common Applications
- Identifying unmarked or unknown capacitors from component bins
- PCB component selection and procurement
- Circuit repair and component replacement
- Electronics education and lab work
- Verifying capacitor values without measurement equipment