They Tested 40 Phones for 2 Years — The Fast Charging Debate Is Finally Over

A massive two-year experiment by YouTube channel HTX Studio has put one of the most debated smartphone myths to rest—that fast charging damages your battery.

After testing 40 phones over multiple trials, the channel found that the difference between fast and slow charging is almost negligible, even after 500 charge cycles.

In the final six-month test, HTX Studio used iPhone 12 and Android devices, splitting them into groups: one charged quickly, one slowly, and another kept between 30% and 80%.

After 500 full cycles — equal to roughly a year and a half of daily use — iPhones charged slowly lost 11.8% capacity, while those fast-charged lost 12.3%, a difference of just 0.5%. On Android, slow-charged phones actually did slightly better, losing 8.8% compared to 8.5% for fast charging.

The team also confirmed that keeping your battery between 30% and 80% helps slightly, but only by a few percentage points, and that leaving your phone plugged in at 100% for days doesn’t cause measurable harm.

When it comes to real-world performance, battery wear doesn’t slow down your phone much — but once health drops below 85%, you’ll notice shorter battery life. At around 80%, it’s time for a replacement.

In short, HTX Studio’s data shows you can fast charge your phone without worry. The best charging method? Simply the one that fits your lifestyle–just charge your darn battery and move on with your life.

Watch HTX Studio’s full 2-year fast charging test on YouTube for a deeper look at how they pulled it off — complete with plants, robotic arms, and plenty of patience: