🔋 Capacitor Code Calculator
Convert a ceramic capacitor code (104, 472, 220...) into pF, nF and µF, or find the 3-digit code from a value. Everything runs in your browser — no data leaves this page.
What is a Ceramic Capacitor Code and How Do You Read It?
Small ceramic capacitors are too tiny to print the full value on, so the capacitance is usually marked with a 3-digit capacitor code. The first two digits are the significant figures and the third digit is the multiplier (10 to the power n); the result is always in picofarads (pF). With this capacitor code calculator you enter the code and instantly see the value in pF, nF and µF, or enter a value and get the matching 3-digit code. Every calculation happens in your browser; no data is ever sent to a server.
The 3-digit code system and a worked example
Take the most commonly confused example, 104: the first two digits (10) are the significant value and the third digit (4) is the multiplier 10⁴ = 10000. So the result is 10 × 10000 = 100000 pF, which is 100 nF = 0.1 µF. Another classic is 473: 47 × 10³ = 47000 pF = 47 nF. By the same logic 103 = 10 nF, 105 = 1 µF, 220 = 22 pF (multiplier 10⁰ = 1) and 221 = 220 pF. Two-digit codes have no multiplier — the value is read directly in picofarads.
Tolerance letters
The letter immediately after the code gives the capacitor's tolerance (how far the real value may deviate). The most common are J = ±5%, K = ±10% and M = ±20%. Tighter parts use F = ±1% or G = ±2%, and very small values may use absolute tolerances like D = ±0.5 pF. For example 104K means a 100 nF capacitor with ±10% tolerance, so its real value can be anywhere from 90 nF to 110 nF.
Tips: reading tiny caps and the pF / nF / µF confusion
- Use a magnifier on the print: ceramic capacitor bodies are small and the code is hard to read; good light and a loupe make it much easier.
- Don't confuse pF, nF and µF: 1 µF = 1000 nF = 1,000,000 pF. When a schematic says "104" it means 100 nF, not 104 pF — this is the single most common mistake.
- Watch for codes with a letter as a decimal point: some caps are marked "n10" (0.1 nF), "1n0" (1 nF) or "4n7" (4.7 nF), where the letter acts as the decimal separator. This tool is for the classic 2-3 digit numeric codes.
- Large values use 105/106: 105 = 1 µF, 106 = 10 µF. Above this size the value is usually printed directly on the body.
Frequently Asked Questions
How do I read a capacitor code?
On a 3-digit ceramic capacitor code the first two digits are the significant figures and the third digit is the multiplier (10 to the power n), giving a result in picofarads (pF). For example 104 means 10 × 10⁴ = 100000 pF = 100 nF = 0.1 µF.
What is a 104 capacitor in nF and µF?
The code 104 equals 10 × 10⁴ pF = 100000 pF = 100 nF = 0.1 µF. Likewise 103 = 10 nF, 105 = 1 µF and 473 = 47 nF.
What do capacitor tolerance letters mean?
The letter after the code gives the tolerance (how much the real value may deviate): J = ±5%, K = ±10%, M = ±20%, F = ±1%, G = ±2%, D = ±0.5 pF, Z = +80% / −20%. For example 104K is a 100 nF capacitor with ±10% tolerance.
How do I read a 2-digit capacitor code?
Some small capacitors have no multiplier and the code is simply the value in picofarads. For example 22 = 22 pF, 47 = 47 pF, 68 = 68 pF. If you enter a 2-digit code here the multiplier is treated as 10⁰ = 1.