• Ceramic disc capacitors have two to three digits code printed on them.

• The first two numbers describe the value of the capacitor and the third number is the number of zeros in the multiplier.

• When the first two numbers are multiplied with the multiplier, the resulting value is the value of the capacitor in picofarads.

• If there is only two number, it means there is no multiplier, Then you just read the value of the first two numbers in picofarads.

• If any capacitor has 10 printed on it- Then its value is 10 PF

• When Any capacitor has 104 printed- It has a multiplier of 4 (Third number of code ). 10 is multiplied by 10×10^{4 }=10000. Then its value is 10×10000= 100000PF

The last number is the power of 10 and multiply with first two no.

If a capacitor has 682 code – first check the last no, here last no is 2. Now the multiplier is 10^{2 }

For example—

204= 20×10^{4 }=200000 PF

472=47×10^{2 }= 4700 PF

502=52×10^{2 }=5200 PF

330=33×10^{0 }=33 PF [10^{0 }= 1]

Here is a Table of Mostly Used Codes of Ceramic Capacitor and their unit conversion in Micro, Nano, and Picofarad

Codes of Polyester Film and Metallized Film Capacitor

If a capacitor is marked with 2A474J, the capacitance is decoded as described above, the two first signs is the voltage rating and can be decoded from the table given below here. 2A is a 100VDC rating according to the EIA (Electronic Industries Alliance) standard.

A second letter will be a temperature coefficient if it’s present.

Some capacitors are only marked as 0.1 or 0.01, mostly in these cases the values are given in uF.

Some small capacitance capacitors can be marked with an R between numbers. If code is 3R9 then R is an indicator of values Less than 10pF and has nothing to do with resistance. 3R9 would be 3.9pF.

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7 thoughts on “Very Simple Method to Read Value of Capacitor”

B21 (CBB21) is not capacitor value, this is material specification of capacitor given by manufacturer.
CBB21 denoted Metalized Polypropylene Film capacitor, This is also a type ceramic capacitor

can u please tell how to identify the values of smd ceramic chip capacitors

What would the capacitance be for a small through-hole ceramic cap with the code B21 and a horizontal under the code?

B21 (CBB21) is not capacitor value, this is material specification of capacitor given by manufacturer.

CBB21 denoted Metalized Polypropylene Film capacitor, This is also a type ceramic capacitor

Very interesting information!Perfect just what I was looking for!

This is a great tip especially to those new to the blogosphere. Simple but very precise info… Appreciate your sharing this one. A must read post!

“502=52×10^2”

Wouldn’t 502 become 50×10^2?

Yes, you are right.

I am sorry for the mistake.

This mistake is now corrected