Capacitor Calculator

Written by Great Medico

Updated September 25, 2026 •2 min read

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Small changes can matter a lot in capacitor. Electronics calculations often mix small component values with high switching frequencies, so prefixes such as µ, m, k, and M deserve careful attention. Use the calculator as a transparent first model, then decide whether your real system needs a more detailed treatment.

What this calculator does

Use this page to evaluate capacitance from Code, Capacity. The result is most useful when the entered quantities describe one consistent physical setup and the displayed units stay attached to the number.

How to use it

Use measured, specified, or deliberately hypothetical values for Code, Capacity. Set Tolerance code, Tolerance capacity to match the solve path you want. Keep the quantity definitions and unit prefixes exactly as labeled; a correct number in the wrong physical quantity or prefix will still produce a misleading result.

How the calculation works

A three-digit capacitor code uses the first two digits as significant figures and the third as the power-of-ten multiplier in picofarads. For example, 104 means 10×10⁴ pF = 100,000 pF = 0.1 µF.

Example

With the default setup (Code = 104; Tolerance code = K ±10%; Capacity = 0.1 µF; Tolerance capacity = ±10%), the page reports capacitance of 100,000 pF. Treat the example as a consistency check, not a universal design target; its meaning depends on the inputs and assumptions above.

How to interpret the result

Treat the capacitance as an ideal circuit-design quantity for the entered topology and values. It is most useful for first-pass component sizing or comparison, followed by checks against ratings, tolerances, ripple, losses, and thermal behavior.

Limitations and notes

Real circuits include switch and diode losses, ESR/ESL, ripple, tolerances, thermal limits, control-loop behavior, transients, electromagnetic interference, and manufacturer derating that ideal equations may not capture. Pay particular attention to Code, Capacity and their units. A mathematically correct result can still be incomplete when the real system includes effects not represented on the form.