There is no answer to what you should buy. Get whatever you want. So yes, you can use a 60W power adapter because it isn't a charger. It is a power supply. There's no such thing as an external charger. The charger is inside of the iPhone, and it will never take any more than 18.5W out of any power adapter, including a 60W power adapter. So a 60W power adapter is ABLE to supply 60W, but it doesn't push the power into the device. The device "pulls" the power out of whatever power adapter it's plugged into, and in the case of iPhone 11, it can't "pull" any more than 18.5W. Yes, it's safe to always do Fast Charging. If it weren't safe, then it wouldn't be possible to do it. I think it's simple logic. Too many people think it's not safe and so they think that it degrades the battery far faster, but it's just The Placebo Effect, meaning it's just their imagination. I've been using an 18W power adapter since I got my iPhone 11 in 2019 and my Maximum Capacity is at 87%. Yes, it's at 87% after over 3.5 years and I only do Fast Charging. Just use whatever power adapter you want and don't worry about it. The way you use your iPhone has a far greater impact on how quickly the battery "degrades" than what power adapter you use or how you charge your iPhone. Heavier iPhone use degrades a battery much faster than light iPhone use because heavier iPhone use means you have to recharge it far more frequently, and the fastest way to degrade a battery is by frequently discharging and recharging it. It doesn't matter if you're using the 5W power adapter to do the "slow" 5W charging or if you always do Fast Charging: the more often you have to recharge the battery, the faster its maximum charge capacity will drop (which is what most people incorrectly call "Battery Health"). So use whatever size power adapter you want and just enjoy your iPhone. Don't worry about how you charge it or anything like that. Just use your iPhone and focus on enjoying life. Don't fall victim to Battery Anxiety. More on reddit.com

The iPhone 11 lineup only support up to 18W (except the Pro Max, which has 20W, but that doesn't really matter). Getting a 30-35W charger won't improve it, so if the 20W one is cheaper: get that.

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The iPhone 11 Pro literally came with it in the box. 18W was the official standard for fast charging for a few years. It’s great if you charge your phone during the day and want it to charge quickly, and will be great with your 11. If you charge overnight with it, just enable optimized battery charging to limit the time it spends over 80% since you’re concerned about long-term battery capacity.

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I’ve been using 20w power brick for almost 4 months now and my 8-month old iPhone 11’s battery health is still at 100%. Just don’t drain ur batt. Draining usually degrades batt health.

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