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Free Battery Tools
& Calculators

Diagnose battery issues, calculate charging times, and size your solar system — all for free, no account required.

Tools Available

Calculators

Crunch the numbers on charging, runtime, and battery life

Calculate how long it takes to charge your device from any percentage to full.

Find the right battery bank size for your solar system based on daily usage.

Estimate how many hours your laptop will last on a full charge.

Check how many charge cycles your battery has left and when to replace it.

Interactive flows to diagnose battery & charging problems

Is your battery dying? Answer 8 quick questions for an instant health score.

Why won't your phone charge? Walk through a guided diagnostic in 60 seconds.

We’re always building new tools. If there’s a calculator or diagnostic you’d find useful, let us know!