Battery Health Lab

Free · Private · No installation

Laptop Battery Health Checker for Windows 11

Turn a confusing Windows battery report into a clear health percentage, wear level and practical next step. Your report is processed locally in your browser.

Check battery health How to create a report
  • Nothing installed
  • No account required
  • Report stays on your device

Battery analyzer

Check your reported battery health

Use a Windows battery report for the fullest result, or enter two capacity values manually.

Drop your battery-report.html here

or choose the HTML file generated by Windows

HTML only · Maximum 10 MB · Processed locally

Built into Windows

Create a battery report in under a minute

Windows 11 can generate the HTML report without third-party software.

  1. 1
    Open Command Prompt

    Search for Command Prompt, right-click it and choose Run as administrator.

  2. 2
    Run the battery report command
    powercfg /batteryreport
  3. 3
    Open the generated file

    Windows displays its saved location. Find battery-report.html, then upload it above.

Simple by design

What the checker reads

The tool extracts only the battery fields needed to explain reported capacity.

01

Capacity values

Design Capacity is compared with Full Charge Capacity to calculate the reported health percentage and wear.

02

Cycle count

If Windows provides a cycle count, it is shown as supporting context rather than treated as a universal pass-or-fail number.

03

Capacity history

Available history points are converted into a simple trend so sudden changes or gradual decline are easier to notice.

Your report stays in your browser

Battery Health Lab reads the selected file with browser JavaScript. The report is not sent to our server or stored by this tool.

Interpret carefully

What is a good laptop battery health percentage?

Capacity health is useful, but runtime, temperature, calibration and physical condition also matter.

Read the complete percentage guide →
90–100% · Excellent

Reported capacity remains close to the original design value.

80–89% · Good

Normal wear is present, but the battery can still be practical for everyday use.

70–79% · Fair

Reduced runtime is likely. Monitor the trend and plan around shorter unplugged use.

60–69% · Worn

Capacity loss is substantial. Replacement may be worthwhile if runtime affects your work.

Below 60% · Replace soon

Confirm the reading after calibration and consider professional inspection or replacement.

Practical guides

Understand the numbers before taking action

Windows 11

How to check laptop battery health in Windows 11

Generate the report, calculate capacity health and avoid common interpretation mistakes.

Read guide → Battery report

How to read every important battery report section

Learn what capacity, usage history, cycle count and estimates can tell you.

Read guide → Health ranges

What battery health percentage is considered good?

Use capacity percentages as context rather than a one-number diagnosis.

Read guide → Replacement

When should you replace a laptop battery?

Combine capacity, runtime, symptoms and safety signs before deciding.

Read guide →

Frequently asked questions

Laptop battery health FAQ

Does this tool upload my battery report?

No. The selected HTML file is read locally by JavaScript in your browser. This version of the checker does not transmit or store the report.

How is battery health calculated?

Reported capacity health equals Full Charge Capacity divided by Design Capacity, multiplied by 100. A result above 100% can occur after battery replacement, firmware changes or imperfect calibration.

Is 80% battery health bad?

Not necessarily. It means the battery reports about 80% of its original capacity. Runtime will be shorter, but replacement depends on your needs and any physical or reliability symptoms.

Why is cycle count missing?

Some laptop firmware does not expose cycle count to Windows. A blank value does not mean the battery has completed zero cycles.

Can this detect a swollen or unsafe battery?

No. Stop using a device if the battery is swollen, unusually hot, leaking, producing an odor or deforming the case. Capacity data cannot rule out a safety problem.

Does it work with Windows 10?

Yes, if Windows generates a compatible battery-report HTML file. The interface focuses on Windows 11 because that is the current primary search and support context.

Method and sources

Based on Windows-reported capacity data

Microsoft documents powercfg /batteryreport as a built-in way to generate an HTML report of battery usage characteristics. Read Microsoft’s battery-care guidance and the Powercfg documentation.