Is the Battery Backup Calculator free to use?

Yes. Every tool on the site is completely free, with no account, login or download required.

Most tools process content on your device. Features using live data, external services or sharing make network requests. Review the tool's instructions and our Privacy Policy before using sensitive information.

Does it work on mobile?

The layout adapts to phones, tablets and desktops. Available file formats, device access and larger processing jobs depend on your browser and device.

Do I need to install anything?

No installation is needed to use the website. The optional browser extension and mobile app are currently in development.

Battery Backup Calculator

Size backup energy and amp-hour capacity from continuous load, runtime, inverter efficiency and reserve.

Backup Load Schedule

Use project or equipment values from the actual specification whenever possible.

Continuous LoadWRequired RuntimehrInverter Efficiency%Reserve%Battery Bank VoltageV

Minimum Rated Storage

2.67 kWh

Energy Delivered To Loads: 2,000 Wh
Battery-Bank Capacity: 55.56 Ah at 48 V

Planning estimate only. Battery chemistry, surge current, temperature, inverter idle draw, age, code and manufacturer limits affect a real system.

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What Is the Battery Backup Calculator?

The Battery Backup Calculator lets you size backup energy and amp-hour capacity from continuous load, runtime, inverter efficiency and reserve. Open the workspace above to use its controls. No account or installation is required.

How It Works

Enter the values or content requested by the Battery Backup Calculator, choose the available options, and review the result. Where a tool offers a download or copy control, use it to keep your work. Live data, remote resources and some device features require an internet connection or browser permission.

When to Use It

Use the Battery Backup Calculator to size backup energy and amp-hour capacity from continuous load, runtime, inverter efficiency and reserve. Explore related home & property for the next step in your workflow. Check units, source values and any stated limitations before relying on a result.

Frequently Asked Questions

Is the Battery Backup Calculator free to use?: Yes. Every tool on the site is completely free, with no account, login or download required.
Is my data private?: Most tools process content on your device. Features using live data, external services or sharing make network requests. Review the tool's instructions and our Privacy Policy before using sensitive information.
Does it work on mobile?: The layout adapts to phones, tablets and desktops. Available file formats, device access and larger processing jobs depend on your browser and device.
Do I need to install anything?: No installation is needed to use the website. The optional browser extension and mobile app are currently in development.

Found an issue? Send Feedback. See our data sources and update policy for tools that depend on changing information.