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Capacitor code calculator (decoder)

The three-digit code printed on a ceramic capacitor is picofarads: the first two digits times ten to the third. Enter the code (104 → 100 nF) and get the value in pF, nF and µF.

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The Capacitor code calculator (decoder) turns Capacitor code (e.g. 104) into Value (pF), Value (nF), Value (µF), instantly and for free. For instance, with Capacitor code (e.g. 104) = 104 it returns Value (pF) = 100,000, Value (nF) = 100 and Value (µF) = 0.1.

How to use it

  1. Enter your values: Capacitor code (e.g. 104).
  2. Read the result instantly: Value (pF), Value (nF), Value (µF).

Frequently asked questions

What does the Capacitor code calculator (decoder) actually compute?

It takes Capacitor code (e.g. 104) and derives Value (pF), Value (nF) and Value (µF) from them. The calculation is live as you type, so the result updates on every change.

What information do I need to provide?

A single value: Capacitor code (e.g. 104). Nothing else is required — no account, no file upload.

Can you show a worked example?

With Capacitor code (e.g. 104) = 104, the calculator returns Value (pF) = 100,000, Value (nF) = 100 and Value (µF) = 0.1. Those figures come from running this exact tool, so you can reproduce them by entering the same values.

What happens if I enter larger values?

It moves a lot. Using Capacitor code (e.g. 104) = 208 instead, Value (pF) goes from 100,000 to 2,000,000,000 — which is why it is worth testing a few scenarios rather than trusting a single figure.

What does it give for smaller values?

Scaled down to Capacitor code (e.g. 104) = 52, Value (pF) comes out at 52. The relationship is worth checking at both ends before you rely on a single result.

When would I actually use this?

At the bench: sizing a resistor for an LED, reading a colour band, working out a divider ratio, and checking a part will not cook.

What is the most common mistake?

Choosing a resistance and forgetting the power rating. A value that is electrically right will still burn if the package cannot dissipate what passes through it — check the watts as well as the ohms.

What is the difference between the Capacitor code calculator (decoder) and the Resistor Color Code Calculator?

This one returns Value (pF) and Value (nF); the Resistor Color Code Calculator returns Result. That is the whole difference — open the one whose figure you need.

Is there a tool for the next step?

Capacitor energy calculator is the closest one after this: Compute the energy stored in a capacitor from its capacitance and voltage (E = ½CV²).

What else is worth having open alongside it?

Series capacitor calculator and 555 timer calculator (astable & monostable) — they come up in the same task often enough to be worth a second tab.

Further reading

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