If a laptop drains quickly, record capacity and usage conditions separately. A Windows 11 battery report is a starting point, but one number cannot decide replacement timing or how many hours you will get.
Generate the report and use its actual path
Microsoft’s instructions use an administrator Command Prompt and powercfg /batteryreport. Read the generated HTML file location, then open it through File Explorer. Use the path shown on your computer rather than copying someone else’s example path.
Record both capacities in the same unit
Design Capacity estimates the capacity of a new battery of that type; Full Charge Capacity refers to capacity at full charge. Controller values may be unavailable. Do not turn a missing field into zero.
| Record | Fictional value |
|---|---|
| Design Capacity | 50,000mWh |
| Full Charge Capacity | 40,000mWh |
| Simple capacity ratio | 40,000 ÷ 50,000 × 100 = 80% |
80% capacity is not an 80% runtime promise
The ratio compares those two values. Brightness, programs and workload are not guaranteed to match earlier use. Do not turn five old hours into exactly four current hours. Record report date, task and observed duration for a more useful support conversation.
A worked example
Fictional worksheet: record report date and both capacities, then put video viewing and document work durations in separate rows. Compare the same fields in older reports when available; one reading is not a lifespan forecast or replacement threshold.
Common questions
Where is the report?
Use the location shown after the command runs.
Does a missing value prove failure?
A value may not be reported. Do not calculate it as zero; ask the manufacturer.