How to check wireless charging rate for a festival

You want your phone ready for tickets, maps, photos, and messages during a festival. A wireless pad may show that it is charging, but that does not tell you how quickly the battery is gaining charge in your actual setup.

Use the Charger & Cable Test on the phone you plan to take. It can show a reported charging rate in percent per minute, if your phone's browser reports battery information. This helps you compare setups, but it does not measure the charger's electrical output in watts.

Test your wireless charger

1. Open the Charger & Cable Test on the phone you will use at the festival. The test must run on the phone being charged, and it appears only when the browser reports a battery.
2. Connect the wireless charging pad to the power adapter and outlet you plan to use. Check that the phone shows it is charging, then place it in the usual position on the pad.
3. Start with the battery between about 20% and 70%. Let the phone cool if it feels warm, and avoid testing near a full battery because charging often slows as the battery fills.
4. Keep the phone in place and avoid using it for 10 to 15 minutes. Observe the reported rate and whether the battery percentage rises. If the browser needs to stay open to show the reading, keep the screen brightness and activity consistent across comparisons.
5. Repeat the test with one change at a time, such as removing the case or using a different power adapter. Return the battery to a similar starting percentage and let the phone cool before comparing.

For a useful festival check, test the setup as you intend to use it. If you plan to charge through a case, include that case in your first test. You can then run a second test without it to see whether it makes a difference.

What the result means

The rate is positive and the battery percentage rises

The phone is gaining charge in this setup. A steady reading is a good sign, but treat it as an estimate for the conditions you tested, not a promise of how much charge you will gain in every situation.

The rate is low or changes from moment to moment

Wireless charging can slow when the phone is warm, poorly positioned, in a thick case, or being used at the same time. The phone may also reduce charging speed as its battery level rises. Repeat the test at a similar battery level and temperature before deciding the pad is underperforming.

The rate stays at zero or the battery percentage does not rise

The phone may not be charging, or its browser may not report charging data. Check the phone's charging indicator and reposition it on the pad. If the indicator confirms charging but the test shows no rate, the browser may not support the battery information the test needs.

The browser does not show the test

Battery reporting is not available in every phone browser. The test cannot make a charging-rate reading if the browser does not expose battery information. Use the phone's on-screen charging indicator as a basic check, or compare the battery percentage before and after a timed interval with the same setup.

How to improve a slow or inconsistent result

1. Center the phone on the pad. Move it slowly until the charging indicator appears and stays on. A small change in position can affect the charging connection.
2. Check the case and attachments. Remove a thick case, metal plate, card holder, or magnetic accessory for a comparison. If removing one improves the rate, check whether the phone and case are suitable for wireless charging before using the case at the event.
3. Use the power adapter recommended for the pad. A pad's charging speed depends on both the pad and the power source feeding it. Try the adapter and cable specified by the pad's manufacturer, then compare again under the same conditions.
4. Reduce heat and phone use. Stop navigation, video playback, games, and other demanding tasks while testing. Keep the phone and pad out of direct sun, and let them cool before a repeat test.
5. Check the phone's battery settings. On Android, open Settings › Battery, or on some Samsung phones, Settings › Battery and device care › Battery. On iPhone, open Settings › Battery. Battery protection or optimized charging features may affect behavior near a charge limit, so compare at a lower battery level too.
6. Test one part at a time. If possible, compare a different compatible pad or power adapter with the same phone. Then test your pad with another compatible phone. This helps separate a phone issue from a pad or power-source issue.

When the charger or phone may be faulty

If the pad repeatedly stops charging, the phone heats unusually, or the charging indicator flickers when the phone is positioned correctly, stop the test and disconnect the pad. Check the cable and adapter for visible damage, and follow the pad maker's safety instructions.

If another compatible phone also fails on the pad with the recommended power source, the pad or its cable may need replacement or warranty service. If your phone fails on several known-working pads, have the phone checked by its manufacturer or a repair shop.

What percent per minute can and cannot tell you

A percent-per-minute result describes the battery's reported change over time. It is useful for comparing the same phone in similar conditions, but it is not a direct reading of power in watts. Phones have different battery capacities, and battery software can change the rate as charge level and temperature change.

For festival planning, use the result as a practical comparison: does this setup add charge during a short break, and does it keep charging reliably with the case and power source you will bring? Leave extra time and keep a backup charging option if your phone is important for access, directions, or contacting others.