Draft for review — not published. Course data: EmptyCore External Courses, finalised 27 Oct 2026.
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Tool 10 of 13 · Component codes

Capacitor code calculator

Decode the three-digit code printed on ceramic and film capacitors — such as 104, 103, 472J or 2A223K — into pF, nF and µF, including tolerance and voltage letters. Or enter a capacitance to find its code.

Calculator

Enter your values

Small ceramic and film capacitors print a short code instead of the value. Decode it here, or find the code for a value.

Direction
Examples: 104, 472J, 2A223K, 4R7, 0.1

Result

FormulaCode ABC = AB × 10C pF104 = 10 × 10⁴ pF = 100 nFC = 8 → ×0.01 · C = 9 → ×0.1Voltage prefix: 1H = 50 V, 2A = 100 V

Coro's tip: The 3-digit code is always in picofarads. 1000 pF = 1 nF and 1000 nF = 1 µF. Big electrolytic capacitors simply print the value, like 470µF 25V. Never use one above its voltage rating.

Capacitor code calculator: common questions

What does 104 mean on a capacitor?

10 followed by four zeros picofarads: 100,000 pF = 100 nF = 0.1 µF.

What unit is a capacitor code in?

The three-digit code is always in picofarads (pF). 1000 pF = 1 nF and 1000 nF = 1 µF.

What do the letters J, K and M mean?

They are the tolerance: J = ±5%, K = ±10%, M = ±20%.

For learning and low-voltage hobby circuits (12 V and below). Always check the part's datasheet. Never use these tools to plan mains (230 V) wiring.

Want to really understand these formulas?

EC-01 Basic Electronics teaches all of this on real hardware — from Ohm's law to a soldered 555 flasher.

Results update as you type. Done here? Pick another calculator any time.
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