SMD Capacitor Code Calculator
The surface mount capacitor code calculator can determine the capacitance value and tolerance by inputting the 3/4 digit or alphabetical code found on the device.
Choose the code type, three-or-four-digit EIA or EIA-198, then select the markings from the table below.
Understanding SMD Capacitor Marking Systems
Surface Mount Device (SMD) capacitors, especially multi-layer ceramic capacitors (MLCC), are often too small to have their values printed directly in a human-readable format like “10µF”. To solve this, industry standards were developed to compress information into 3 or 4 characters.
Using an SMD Capacitor Code Calculator is the most reliable way to avoid manual calculation errors, especially when dealing with different marking standards.
How to Read SMD Capacitor Codes
Depending on the precision and the manufacturing standard, you will typically encounter three types of marking systems:
1. The 3-Digit System (Standard Tolerance)
This is the most common marking for standard capacitors.
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The first two digits represent the significant figures of the value.
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The third digit is the multiplier (the power of 10).
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The base unit is always picofarads (pF).
2. The 4-Digit System (High Precision)
Used for high-tolerance or specialized capacitors where an extra digit of precision is required.
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The first three digits are the significant figures.
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The fourth digit is the multiplier.
3. The EIA-198 Standard (Alpha-Numeric)
The EIA-198 system uses a letter followed by a number. This is a highly compressed format:
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The Letter represents a specific two-digit value (e.g.,
A = 1.0,S = 4.7). -
The Number represents the multiplier (power of 10).
Understanding Tolerance Codes
Sometimes, a letter is added to the end of the numerical code to indicate the Tolerance (how much the actual capacitance can deviate from the nominal value).
| Letter Code | Tolerance |
| B | ±0.10 pF |
| C | ±0.25 pF |
| D | ±0.50 pF |
| F | ±1% |
| G | ±2% |
| J | ±5% |
| K | ±10% |
| M | ±20% |
| Z | +80%, -20% |