Use this electronics calculation for a first-pass component, converter, signal, motor, or sensor estimate when the stated operating conditions and units match the device data.

Supply voltage (V)

Required number input.

Capacitance C1 (F)

Required number input.

Capacitance C2 (F)

Required number input.

Compute the voltage across C1 of a series pair as supply volts times C2 / (C1 + C2). The tool evaluates the supplied inputs together and returns the named outputs below; it does not infer omitted operating conditions or change the units shown.^[1]

Voltage across C1 (V)

The resulting voltage across c1 returned as a number.

• Capacitance, ESR, leakage, ripple rating, lifetime, and self-resonance vary with frequency, temperature, DC bias, aging, dielectric, package, and mounting. Nominal capacitance alone does not determine in-circuit impedance or reliability.
• Use finite inputs in the displayed units and preserve more precision than the final presentation requires. Independently verify safety-critical, financial, compliance, or production decisions.

Check the result against the current datasheet and worst-case operating corners, then verify the circuit or measurement with simulation and bench testing where failure matters.

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