Capacitor Energy Calculator
Calculate ideal stored energy and charge from capacitance and voltage.
Your inputs
Calculation results
Formula & assumptions
Energy = CV²/2; charge = CV.
Values use the specified units. Calculations use floating-point arithmetic. Check input measurements and formula assumptions before applying the result.
Compare your scenarios
Save up to five results to compare changes side by side. Scenarios stay in this tab until you clear or reload it.
Using Capacitor Energy Calculator
Calculate ideal stored energy and charge from capacitance and voltage.
- Enter capacitance, voltage using the units printed under each field.
- Choose Calculate, or enable live updates. Review the result labels and formula assumptions.
- Save scenarios to compare up to five variations, then copy the report or download JSON or CSV.
Example
Capacitance: 1000 microfarads Voltage: 12 volts Stored energy · joules: 0.072 Charge · coulombs: 0.012
Questions & answers
What does Capacitor Energy Calculator calculate?
Calculate ideal stored energy and charge from capacitance and voltage.
Which units should I enter?
Capacitance uses microfarads. Voltage uses volts. Convert values to these units before calculating.
Which formula does it use?
Energy = CV²/2; charge = CV.
What does the included example show?
Capacitance: 1000 microfarads; Voltage: 12 volts. Result: Stored energy · joules = 0.072; Charge · coulombs = 0.012.
Can I compare different settings?
Yes. Save a scenario, change the inputs and save another result. Up to five scenarios are compared in this tab; they disappear when you reload or leave.
Can I export the calculation?
Copy the JSON report or download JSON and CSV with inputs, result labels and numeric values. Processing uses local JavaScript; no calculation request is sent to our server. Displayed values use up to 10 significant digits; exports retain JavaScript numeric precision.
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