How this calculator works
For the common three-digit picofarad marking, the first two digits are a number and the third is a power-of-ten multiplier. The tolerance letter is separate: B, C and D are absolute picofarad tolerances, while the other offered letters are relative tolerances. Encoding requires an exactly representable value. The charge modes instead use Q = CV and do not interpret a package marking. Manufacturers can use other marking systems, so verify an unfamiliar code against its datasheet.
Formula
C = (first two digits) × 10^(third digit) pF. Relative limits: Cmin = C(1-tlow), Cmax = C(1+thigh). Stored charge: Q = C V.
Worked example
Code 104 means 10 × 10^4 pF = 100 nF. With K tolerance its range is 90 to 110 nF. A 47 nF value encodes as 473; J tolerance gives 44.65 to 49.35 nF.
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Frequently asked questions
Does K mean kilofarads?
No. In this position K is the tolerance letter for +/-10%. The numerical marking establishes capacitance.
What does a leading zero mean?
The text input preserves all three digits. The first two digits are still interpreted together, so 010 represents 1 pF in the stated scheme.
Can I use this for any surface-mount code?
No. Two-character EIA markings, dielectric codes and manufacturer part codes use other systems. This page explicitly implements the three-digit picofarad scheme.