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Compare battery life using the same independent test method, then check whether the workload and test setup resemble how you use a phone. A manufacturer’s “up to” hours usually describe a defined test, not a guarantee of your daily runtime. Battery capacity in mAh is useful context, but it cannot be converted directly into hours.
Start by identifying what the battery-life number measures
“Battery life” can mean local video playback, streamed video, web browsing, talk time, gaming, or a mixed-use estimate. These workloads draw power differently, so a result is useful only when you know what was tested.
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Local video playback may avoid the data connection involved in streaming. Streaming can also use the phone’s network radio, so its result is not directly interchangeable with local playback. Apple describes separate procedures for local and streamed video in its battery testing notes. Samsung likewise lists separate talk, audio, video, and internet-use procedures in its battery test procedure.
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Look for the exact workload beside every runtime claim. If a listing says only “up to 20 hours,” without explaining what activity, connection, and setup produced that figure, it is not enough to compare phones reliably.
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Compare phones tested by the same method
The fairest comparison is a side-by-side test from one outlet that put the candidate phones through the same procedure. Do not rank a manufacturer’s video-playback claim against a reviewer’s web-browsing result as if they measured the same thing.
Testing outlets often separate workloads. PhoneArena says it runs in-house web-browsing, video-streaming, and 3D-gaming tests; its streaming test uses the same playlist and settings across devices, while its gaming test uses a real game under tuned settings. Its results page presents separate runtimes alongside battery capacity.
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Android Authority describes automated testing across web browsing, video playback, camera capture, video recording, video calls, and graphics benchmarking data. It drains 7% per workload test and extrapolates the maximum task runtime from that segment. This is a method detail, not a prediction that a phone will last that many hours in mixed daily use. See its battery testing methodology.
Different outlets can use different brightness levels, test loops, network conditions, or extrapolation methods. Treat their figures as separate evidence, not a precise league table, unless the procedures are demonstrably comparable.
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Match the workload to your routine
Choose tests that reflect the activities most likely to drain your own phone. A continuous screen-on test may tell you little about a day spent mostly on standby, while a local video loop may not represent streaming over cellular.
- Frequent streaming: look for streamed-video results, and check whether testing used Wi-Fi or cellular.
- Gaming: prioritize gaming results; graphics-heavy play can behave differently from browsing or video playback.
- Photos and video: look for camera capture and video-recording tests.
- Video calls: seek a video-call workload rather than assuming a video-playback figure predicts it.
- Mixed daily use: use a transparent mixed-use test if available, alongside task-specific results.
Apple’s disclosed representative-use profile combines passive and active activities such as messaging, photos, music, social media, video, games, web browsing, and navigation. That kind of profile may be more relevant to a varied day than a single continuous task, but it still represents a defined test rather than your exact habits.
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Check the conditions behind the result
Before trusting a runtime, see whether the source identifies the test settings and device state. Brightness, Wi-Fi versus cellular, signal strength, temperature, software, and battery age can all affect runtime. A new-device lab result may not predict an older used phone or a commute through weak-signal areas.
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- Was screen brightness specified or calibrated consistently?
- Was the phone on Wi-Fi or cellular, and what signal conditions applied?
- For streaming, what service or media source was used?
- Were audio, refresh rate, power-saving settings, and other settings controlled?
- Was the unit retail hardware with public software, or a development-stage device?
Apple’s test notes describe network subscriptions, repeated media duration, software and device generation, and setting exceptions. Samsung says its 2025 procedure used a lab, simulated network, and development-stage prototypes and software. Its practical warning is apt: “The battery lifetime changes according to the device setting method and method of use.” PhoneArena also points to signal strength, temperature, and battery aging as real-world variables.
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Use mAh and battery labels as supporting evidence
mAh describes battery charge capacity, but it does not tell you how many hours the complete phone will last under a particular task. The screen, processor, radios, software, and workload all affect energy use. Compare capacity alongside comparable runtime tests; do not treat a larger mAh figure as an automatic guarantee of longer endurance.
For example, PhoneArena’s result listing for the OnePlus 13, dated January 7, 2025, shows a 6,000 mAh capacity alongside 7h 30min of web browsing, 21h 34min of video, and 9h 12min of gaming. Those are distinct test outcomes, not a forecast for every owner or every regional variant. The different results illustrate why capacity or one headline number cannot represent every use case.
In the EU, the cited regulation defines battery endurance in hours by the execution time of a specified test sequence. Where an energy label applies, check the current label and the rules for the relevant market rather than assuming the same label requirements apply everywhere. See the EU smartphone energy-labelling regulation.
Quick Recap
A practical comparison checklist
- List your likely heavy tasks. Note whether streaming, gaming, photography, video calls, or standby matters most.
- Find results for those workloads. Prefer one independent source that tested all your candidate phones using a shared method.
- Read the test conditions. Check brightness, network, signal, settings, software, and whether the device was new or preproduction.
- Compare like with like. Put the same workload side by side. Keep streaming separate from local playback and do not mix methods as though they were equivalent.
- Use capacity and labels for context. Treat mAh and any applicable standardized label as additional information, not a substitute for workload-specific runtime results.
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