C104

Ceramic Capacitor Code Calculator

Turn the number code on a ceramic or film capacitor, such as 104 or 472J, into pF, nF and µF.

Code on the capacitor Find the code for a value F

How to read the code

The unit is picofarads. The first two digits are the value and the third is the number of zeros, so 104 is 10 followed by four zeros: 100,000 pF, which is 100 nF or 0.1 µF. A trailing letter gives the tolerance: J is ±5%, K is ±10% and M is ±20%. Values below 10 pF use R as the decimal point, as in 4R7 for 4.7 pF.

Worked example: a 223K capacitor

The first two digits are 22 and the 3 adds three zeros → 22 × 10³ = 22,000 pF
Convert: 22,000 pF = 22 nF = 0.022 µF
The trailing K means ±10% → 19.8 nF to 24.2 nF

Worked example: a 2A472J film capacitor

The leading 2A is a voltage code: rated for 100 V.
The 472 in the middle is 47 × 10² = 4,700 pF = 4.7 nF.
The trailing J is ±5% → 4.465 nF to 4.935 nF

Capacitor code conversion chart

Code	pF	nF	µF
Code100	10 pF	0.01 nF	0.00001 µF
Code220	22 pF	0.022 nF	0.000022 µF
Code470	47 pF	0.047 nF	0.000047 µF
Code101	100 pF	0.1 nF	0.0001 µF
Code221	220 pF	0.22 nF	0.00022 µF
Code331	330 pF	0.33 nF	0.00033 µF
Code471	470 pF	0.47 nF	0.00047 µF
Code102	1,000 pF	1 nF	0.001 µF
Code222	2,200 pF	2.2 nF	0.0022 µF
Code332	3,300 pF	3.3 nF	0.0033 µF
Code472	4,700 pF	4.7 nF	0.0047 µF
Code103	10,000 pF	10 nF	0.01 µF
Code223	22,000 pF	22 nF	0.022 µF
Code333	33,000 pF	33 nF	0.033 µF
Code473	47,000 pF	47 nF	0.047 µF
Code104	100,000 pF	100 nF	0.1 µF
Code224	220,000 pF	220 nF	0.22 µF
Code474	470,000 pF	470 nF	0.47 µF
Code105	1,000,000 pF	1,000 nF	1 µF
Code106	10,000,000 pF	10,000 nF	10 µF

Tolerance letters

Letter	Tolerance
B	±0.1 pF
C	±0.25 pF
D	±0.5 pF
F	±1%
G	±2%
J	±5%
K	±10%
M	±20%
Z	+80% / −20%

Voltage codes (2A, 1H and so on)

Leading code	Voltage rating
0G	4 V
0J	6.3 V
1A	10 V
1C	16 V
1E	25 V
1V	35 V
1H	50 V
1J	63 V
1K	80 V
2A	100 V
2C	160 V
2D	200 V
2E	250 V
2F	315 V
2G	400 V
2W	450 V
2J	630 V
3A	1000 V

EIA voltage codes printed before the value on film and ceramic capacitors. Codes like 4n7 (4.7 nF) and n47 (470 pF), where the unit letter stands in for the decimal point, also work in the calculator above.

Using it in practice

Step by step

Type the printed code, for example 104 or 472J; a trailing letter is the tolerance.
Read the value in pF, nF and µF together, since schematics and shops use different units.
Check the voltage rating separately; it is printed on its own line or implied by the series, not in the value code.

Common mistakes

Reading the code as picofarads directly. 104 is not 104 pF: it is 10 followed by four zeros, 100 000 pF, which is 100 nF or 0.1 µF.
Mixing up nF and µF in parts lists. 0.1 µF, 100 nF and 104 are the same part. Many US schematics skip nF entirely.
Assuming a ceramic keeps its value. Class 2 ceramics (X7R, X5R and especially Y5V) lose capacitance with DC bias and temperature; a small Y5V part can drop to a fraction of its marked value at its rated voltage.

Tolerance letters

The common letters are J (±5%), K (±10%), M (±20%) and Z (−20% to +80%). Small-value C0G (NP0) parts may use absolute tolerances such as C (±0.25 pF) or D (±0.5 pF). For timing and filter circuits choose C0G or film capacitors; save X7R for decoupling, where the exact value matters less.

Frequently asked questions

What value is a 104 capacitor?

100 nF, which is 0.1 µF. It is the most common decoupling capacitor, placed right next to the power pins of ICs.

What do letters like J, K and M after the code mean?

They give the tolerance: J is ±5%, K is ±10% and M is ±20%. Z means +80% / −20%, common on low-cost ceramic capacitors.