Test a phone online
Ten quick tests that run in the phone's own browser, in about 5 minutes: the screen, touch, speakers, microphone, cameras, sensors and charging port. Made for checking a used phone before you pay, on any brand.
Open this page on the phone you want to test. You can skip any test, and Back stops at any time.
Or pick one test
What a browser cannot see: whether the phone is really the model it claims (copies run on a different processor), how worn the battery is, whether the storage is as big as it says, and whether the system was modified. The free Knowfone app for Android checks all of that and every part above in about 7 minutes, then answers: good to buy, buy only at a lower price, or don't buy.
Questions
Is the online phone test free?
Yes. All ten tests are free, need no account and run in the browser of the phone you are testing.
Does it work on an iPhone?
Most tests do. iPhones do not let web pages use the vibration motor or see the charger, so those two tests ask you to check by hand.
Is anything uploaded?
No. The camera picture, the sound and the results stay on the phone. The site has no trackers or analytics.
Can a browser tell if a phone is a copy?
Only partly. A refresh rate that is lower than the model's, or fewer cameras, are hints. The real processor, memory, storage and security state need an app: the free Knowfone app for Android compares them with the model the phone claims to be.
More: how to check a used phone before buying, phone test codes by brand and real specs of popular models.