Capacitor Code Calculator

Decode EIA 3-digit markings, decimal codes, and tolerance letters into pF, nF, and µF.

1. Decode Code to Value

e.g. 104K, 4R7

Capacitor Code

Picofarads (pF): 100,000 pF

Nanofarads (nF): 100 nF

Microfarads (µF): 0.1 µF

Tolerance: ±10%

2. Reverse Value Lookup

Value ➔ Code

Capacitance Value & Unit

Calculated 3-Digit Code: 104

How 3-Digit Capacitor Codes Work

Most ceramic and film capacitors use a 3-digit Electronic Industries Alliance (EIA) marking system where the base measurement unit is always picofarads (pF):

First 2 digits: The significant figures of the capacitance value.
3rd digit: The multiplier, representing the exponent (10ⁿ) to multiply the base value by.
Special multipliers: If the 3rd digit is 8, multiply by 0.01; if it is 9, multiply by 0.1.
The letter 'R': Represents a decimal point for values under 10 pF (for example, 4R7 = 4.7 pF).
Optional suffix letter: Indicates manufacturing tolerance (e.g., J = ±5%, K = ±10%, M = ±20%).

Example: 104K

10 × 10⁴ pF = 100,000 pF = 100 nF (0.1 µF). The letter K indicates ±10% tolerance.

Example: 473

47 × 10³ pF = 47,000 pF = 47 nF (0.047 µF). No tolerance specified.

Example: 4R7

The 'R' replaces the decimal mark: 4.7 pF. Commonly seen in high-frequency RF bypass circuits.

Common Capacitor Code Reference Chart

EIA Code	Picofarads (pF)	Nanofarads (nF)	Microfarads (µF)
101	100 pF	0.1 nF	0.0001 µF
102	1,000 pF	1 nF	0.001 µF
103	10,000 pF	10 nF	0.01 µF
104	100,000 pF	100 nF	0.1 µF
105	1,000,000 pF	1,000 nF	1 µF
222	2,200 pF	2.2 nF	0.0022 µF
223	22,000 pF	22 nF	0.022 µF
473	47,000 pF	47 nF	0.047 µF

Frequently Asked Questions (FAQ)

What capacitance value is a 104 capacitor? ▼

A 104 capacitor denotes 100,000 pF, which equals 100 nF or 0.1 µF. It is one of the most widely used decoupling capacitors in digital electronics.

What does the letter after the 3-digit code mean? ▼

The letter specifies the tolerance rating. Common letters include J (±5%), K (±10%), M (±20%), and Z (+80%/-20%). For example, 104K is 0.1 µF with a ±10% margin.

How does this calculator decode voltages or dielectric types? ▼

Voltage and dielectric markings (such as 1H, 2A, or X7R) are non-standard across different manufacturers. Always consult the specific manufacturer's component datasheet for rated voltage and thermal stability.

What does 4R7 mean on a capacitor? ▼

The letter 'R' acts as a decimal point. Therefore, 4R7 represents 4.7 pF. Similarly, 0R5 represents 0.5 pF.

What if the capacitor only has 2 digits printed on it? ▼

Two-digit codes represent their direct value in picofarads (pF). For example, a code of 22 indicates 22 pF, and 47 indicates 47 pF.