What is the difference between X7R, X5R and C0G/NP0?

C0G/NP0 (Class 1) barely changes with temperature and is ideal for timing/filters. X7R/X5R (Class 2) are general purpose (~±15%). Y5V is high capacitance but unstable, for decoupling only.

What do the characters in X7R mean?

1st char = low temperature (X = −55 °C), 2nd = high temperature (7 = +125 °C), 3rd = capacitance change (R = ±15%). So X7R: −55…+125 °C, ±15%.

How do you read a capacitor voltage code like 1H?

The digit is the multiplier (1 = ×10) and the letter the significant figure (H = 5.0): 1H = 50 V. Also 1A = 10 V, 1C = 16 V, 1E = 25 V, 2A = 100 V.

What do 4p7 or 4n7 mean?

The letter gives both the decimal point and the unit: 4p7 = 4.7 pF, 4n7 = 4.7 nF, 2µ2 = 2.2 µF.

How to Read Capacitor Codes (104 = 100 nF, Chart)

Q: Do electrolytic capacitors use this code?

No; electrolytic and tantalum capacitors print the capacitance and voltage directly (e.g. 100 µF 25V) and carry a polarity mark.

Quick reminder: on a 3-digit ceramic capacitor code the value = (first two digits) × 10^{(third digit)} picofarads; 104 = 100 nF. Our Capacitor Code Calculator does that instantly. This article covers the other markings beyond the value code — dielectric, voltage, tolerance and tricky cases — in depth.

How to read the dielectric / temperature code (C0G, X7R, Y5V)

On multilayer ceramic (MLCC) capacitors, a 3-character code states the material class and how much the capacitance drifts over temperature. Class-2 codes (letter–digit–letter) decode like this:

1st char (low temp)	2nd char (high temp)	3rd char (cap. change)
X = −55 °C	5 = +85 °C	R = ±15%
Y = −30 °C	6 = +105 °C	S = ±22%
Z = +10 °C	7 = +125 °C	U = +22 / −56%
	8 = +150 °C	V = +22 / −82%

So X7R = ±15% over −55…+125 °C; X5R = −55…+85 °C; Y5V = −30…+85 °C, +22 / −82% (very unstable). Class-1 codes are different: C0G (NP0) means a near-zero temperature coefficient (~0 ± 30 ppm/°C).

C0G / NP0: timing, oscillators, filters — where the value must stay stable.
X7R / X5R: general-purpose coupling/bypass; reasonably stable.
Y5V / Z5U: decoupling only; capacitance drops sharply with DC voltage and temperature — do NOT use in timing/filters.

The voltage marking

The rated voltage is often printed directly (e.g. 50V, 16V). On tiny MLCCs a coded EIA system is used: the digit is the multiplier (0 = ×1, 1 = ×10, 2 = ×100) and the letter gives the significant figure (A = 1.0, C = 1.6, E = 2.5, H = 5.0, J = 6.3):

Code	Voltage
1A	10 V
1C	16 V
1E	25 V
1H	50 V
2A	100 V
2E	250 V

Rule of thumb: pick a rated voltage at least 1.5–2× the working voltage (MLCC capacitance also falls under DC bias).

The decimal marker: R, p, n, µ

For small values a letter replaces the decimal point and usually also names the unit (IEC marking): 4p7 = 4.7 pF, n47 = 0.47 nF = 470 pF, 4n7 = 4.7 nF, 2µ2 = 2.2 µF. Some makers use R for pF: 4R7 = 4.7 pF.

The tolerance letter — full table

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%

For small values (≤10 pF) the tolerance is absolute pF (B/C/D); for larger values it is a percentage (J/K/M).

When is this code NOT used?

The code system is specific to small ceramics. Electrolytic and tantalum capacitors print the capacitance and voltage directly (e.g. "100 µF 25V") and carry a polarity mark: on aluminum electrolytics the body stripe marks the (−) leg; on tantalums a bar/mark shows the (+) leg. Film capacitors also usually print the value directly.

Reading a faded / unclear code

On heated or old capacitors the print can fade — use a magnifier and good light.
If unsure, measure the value with an LCR meter (or a multimeter's capacitance mode).
Use circuit context: coupling/bypass is usually 100 nF (104); timing uses small pF values.

Use the calculator

To convert the basic 3-digit code to pF/nF/µF, use our Capacitor Code Calculator; interpret the dielectric, voltage and tolerance markings with the tables above.