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Capacitor Code Calculator

Convert

Small ceramic and film capacitors print their value as a compact code instead of a number. The 3-digit EIA code uses two significant digits followed by a multiplier (the number of zeros, in picofarads), so 104 means 10 followed by 4 zeros = 100,000 pF = 100 nF = 0.1 µF. Codes 8 and 9 in the multiplier position mean ×0.01 and ×0.1. An optional trailing letter encodes the tolerance (J = ±5%, K = ±10%, M = ±20%). Capacitors marked with an R use it as a decimal point (4R7 = 4.7 pF). Type a code and this tool shows the capacitance in all three units plus the decoded tolerance.

Capacitance

100 nF

100000 pF · 100 nF · 0.1 µF

Tolerance: K = ±10%

Common codes
Tolerance letters
B±0.10 pF
C±0.25 pF
D±0.5 pF
F±1%
G±2%
H±3%
J±5%
K±10%
M±20%
Z+80% / −20%

3-digit code: first two digits = value, third = number of zeros (in pF). Third digit 8 = ×0.01, 9 = ×0.1. R is a decimal point (4R7 = 4.7 pF). Trailing letter = tolerance.

How to use

  1. Type the printed code, e.g. 104, 473K or 4R7.
  2. Read the capacitance in pF, nF and µF, plus the tolerance if a letter is present.
  3. Tap a common code chip to load it, or check the tolerance-letter table below.

Frequently asked questions

What does 104 mean on a capacitor?
Two significant digits (10) followed by the number of zeros (4): 10 with four zeros = 100,000 pF = 100 nF = 0.1 µF. It is not 104 pF.
What does the R in 4R7 mean?
On small-value capacitors the letter R marks the decimal point, so 4R7 = 4.7 pF and R47 = 0.47 pF. It replaces a decimal that would be easy to miss when printed.
What do the multiplier digits 8 and 9 mean?
They are exceptions: a third digit of 8 means multiply by 0.01 and 9 means multiply by 0.1. So 229 = 22 × 0.1 = 2.2 pF.
What does the letter after the code mean?
It is the tolerance. Common ones are J = ±5%, K = ±10% and M = ±20%; letters like D, C and B give absolute tolerances in pF for very small parts.

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