Enter a capacitance value to find the corresponding SMD code
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Enter multiple SMD codes (one per line) to calculate all values at once
| Letter | Tolerance | Letter | Tolerance |
|---|---|---|---|
| B | ±0.1pF | J | ±5% |
| C | ±0.25pF | K | ±10% |
| D | ±0.5pF | M | ±20% |
| F | ±1% | P | +100%/-0% |
| G | ±2% | Z | +80%/-20% |
| Code | pF | Code | pF | Code | pF | Code | pF |
|---|---|---|---|---|---|---|---|
| A | 1.0 | L | 2.7 | T | 5.1 | a | 2.6 |
| B | 1.1 | M | 3.0 | U | 5.6 | b | 3.5 |
| C | 1.2 | N | 3.3 | V | 6.2 | d | 4.0 |
| D | 1.3 | P | 3.6 | W | 6.8 | e | 4.5 |
| E | 1.5 | Q | 3.9 | X | 7.5 | f | 5.0 |
| F | 1.6 | R | 4.3 | Y | 8.2 | m | 6.0 |
| G | 1.8 | S | 4.7 | Z | 9.1 | n | 7.0 |
| H | 2.0 | - | - | - | - | t | 8.0 |
| J | 2.2 | - | - | - | - | y | 9.0 |
| K | 2.4 | - | - | - | - | - | - |
| Code | Multiplier | Code | Multiplier |
|---|---|---|---|
| 0 | ×1 | 5 | ×100,000 |
| 1 | ×10 | 6 | ×1,000,000 |
| 2 | ×100 | 7 | ×10,000,000 |
| 3 | ×1,000 | 8 | ×100,000,000 |
| 4 | ×10,000 | 9 | ×0.1 |
| Code | Multiplier | Example | Value |
|---|---|---|---|
| 0 | ×1 | 100 | 10 pF |
| 1 | ×10 | 101 | 100 pF |
| 2 | ×100 | 102 | 1,000 pF = 1 nF |
| 3 | ×1,000 | 103 | 10,000 pF = 10 nF |
| 4 | ×10,000 | 104 | 100,000 pF = 0.1 µF |
| 5 | ×100,000 | 105 | 1,000,000 pF = 1 µF |
| 6 | ×1,000,000 | 106 | 10,000,000 pF = 10 µF |
| Package | Dimensions (mm) | Typical Voltage | Capacitance Range |
|---|---|---|---|
| 0201 | 0.6 × 0.3 | 4-16V | 0.1-100 pF |
| 0402 | 1.0 × 0.5 | 6.3-50V | 0.5-10 nF |
| 0603 | 1.6 × 0.8 | 6.3-100V | 1-100 nF |
| 0805 | 2.0 × 1.25 | 6.3-100V | 10 pF-1 µF |
| 1206 | 3.2 × 1.6 | 6.3-100V | 100 pF-10 µF |
| 1210 | 3.2 × 2.5 | 6.3-100V | 1 nF-22 µF |
| 1812 | 4.5 × 3.2 | 6.3-100V | 10 nF-47 µF |
| 2220 | 5.7 × 5.0 | 6.3-100V | 100 nF-100 µF |
104: 10 × 10⁴ = 100,000 pF = 0.1 µF
473: 47 × 10³ = 47,000 pF = 47 nF
102: 10 × 10² = 1,000 pF = 1 nF
220: 22 × 10⁰ = 22 pF
1001J: 100 × 10¹ = 1,000 pF ±5%
4703K: 470 × 10³ = 470,000 pF ±10%
1500F: 150 × 10⁰ = 150 pF ±1%
2202M: 220 × 10² = 22,000 pF ±20%
A5: 1.0 × 100,000 = 100,000 pF = 0.1 µF
S3: 4.7 × 1,000 = 4,700 pF = 4.7 nF
J2: 2.2 × 100 = 220 pF
m4: 6.0 × 10,000 = 60,000 pF = 60 nF
1µF: 1 microfarad
10n: 10 nanofarads
470p: 470 picofarads
2.2µ: 2.2 microfarads
| Date | Type | Code | Value | Actions |
|---|---|---|---|---|
| No calculations yet | ||||
The first thing to know is that most surface-mount ceramic capacitors carry no marking at all. There is no room on an 0402 or 0603 part, and the manufacturing process does not need it — parts arrive on labelled reels and are placed by machine. Once a board is populated, the only reliable way to identify a ceramic capacitor is the bill of materials or a measurement.
Where codes do appear — on larger ceramics, tantalums and electrolytics — the common schemes are:
Tantalum capacitors mark the positive terminal with a bar. Aluminium electrolytics mark the negative terminal with a stripe. The conventions are opposite, which is a classic and expensive mistake — a reversed tantalum can fail short and ignite.
Tantalums in particular need generous derating, commonly to 50% of rated voltage or less, because their failure mode is a short circuit rather than a gradual loss of capacitance. Ceramics do not fail that way, but Class 2 types lose substantial capacitance under DC bias, so a part chosen with little voltage margin also delivers far less capacitance than its marking suggests.
If a board needs a capacitor identified and the BOM is unavailable, measuring with an LCR meter — out of circuit, since parallel components corrupt the reading — is faster and more reliable than decoding a marking that may not exist.
Because there is no room on small packages and the manufacturing process does not require it. Parts are identified by reel labelling and placed by machine, so once a board is built the bill of materials or a measurement is the only reliable identification.
As picofarads: two significant digits followed by the number of zeros. 104 means 100,000 pF, which is 0.1 µF, and 225 means 2.2 µF.
The end with the bar. This is the opposite convention to aluminium electrolytics, where the stripe marks the negative terminal, and confusing the two can cause a tantalum to fail short and ignite.
Commonly to 50% of its rated voltage or less, because its failure mode is a short circuit rather than gradual degradation. Generous margin is a reliability requirement, not conservatism.
Check the bill of materials or assembly drawing first. Failing that, measure it with an LCR meter after removing it from the board, since parallel components distort an in-circuit reading.
Class 2 types often do not. They lose significant capacitance under DC bias and across temperature, so a part operating near its voltage rating may provide a fraction of the marked value.
Written and reviewed by
Lead Electronic Engineer (R&D) · Power Electronics Specialist · M.E. Power Electronics
Founder of Power4All. Works in power-electronics R&D and writes the converter guides, calculators and simulators on this site.
Last updated