How this estimator works
The calculator builds a weighted average current draw from your usage profile (idle, light, medium, heavy), then divides effective battery capacity
(capacity × health) by that draw to estimate runtime. It also computes your expected runtime for a custom charge band like
80% to 20%, which is often more practical than 100% to 0%.
What affects real-world battery life
- Display brightness and refresh rate
- Signal quality (poor network increases power draw)
- Background sync and notifications
- Temperature and battery aging
- Gaming, camera, and navigation workload spikes
How to use this tool effectively
- Start with your battery capacity (for example 4500 or 5000 mAh).
- Set realistic battery health based on your phone age and diagnostics.
- Tune current draw values to match your behavior (gaming, camera, calls, navigation).
- Adjust usage percentages for a typical day. If they do not total 100, the tool auto-normalizes.
- Use charge range mode (for example 90% to 15%) to estimate practical daily runtime.
Practical Android use cases
- Battery budgeting: compare expected life after enabling 120Hz or higher brightness.
- App testing: estimate the impact of background services or frequent location updates.
- Travel planning: estimate whether your current profile can last a full day without charging.
- Optimization checks: model how reducing heavy-use sessions improves total runtime.
Frequently Asked Questions
Is this estimate exact?
No. It is a planning estimate based on average current draw assumptions, not direct hardware telemetry.
How do I pick realistic current draw values?
Start with defaults, then calibrate using your own battery history over a few days for better accuracy.
Why normalize usage percentages?
If percentages don’t add to 100, the tool scales them proportionally so the estimate remains valid.
Why does my real battery life differ from the estimate?
Live network conditions, temperature, app wakeups, and dynamic CPU/GPU spikes can change actual drain significantly.
Does this tool upload my data?
No. All calculations run locally in your browser and no usage profile is uploaded.