5 tools

Inverter calculators

An inverter connects two different electrical worlds: AC loads and a high-current DC battery. These tools keep energy runtime, continuous and surge power, apparent power, conversion loss and battery current visible instead of collapsing them into one watt figure.

Inverter power and sizing

Size continuous output, apparent power and startup surge from the loads that can operate together.

  • Inverter Size Calculator

    Size from the loads that can run together, then check the largest startup event. A single watt total is not enough when motors, compressors or poor power factor are involved.

Battery side

Estimate how long the battery can support the AC load and how much DC current the inverter requires.

  • Inverter Battery Runtime Calculator

    Estimate AC runtime from a battery without treating inverter efficiency or its own idle consumption as free. The result shows the complete battery-side power budget.

  • Inverter DC Current Calculator

    Convert an inverter's AC load into the DC watts and amps the battery must actually supply. Use voltage under load—not only the nominal label—to avoid understating current.

Portable power stations

Keep stored energy, delivered runtime, continuous output and startup surge as separate requirements.

  • Portable Power Station Runtime Calculator

    Estimate how long a portable power station can run a load without assuming every advertised watt-hour reaches the outlet. Capacity and output-power checks are shown separately.

  • Portable Power Station Size Calculator

    Choose a station that passes energy, continuous-power and startup-surge requirements. A large Wh number does not guarantee enough output watts, and a powerful inverter does not guarantee enough runtime.

Methodology

How these tools are built

Every calculator here shows the formula it uses, the assumptions behind it and the limits of the model. Where a figure is a typical published value rather than a specification, it says so and lets you change it.

Read the PowerCalcLab methodology →