I bought a 256GB SSD for an 11-inch MacBook Air (mid-2012), and it was $75. Just make sure you know the model of your MacBook Air, as there were variations from year to year. There are reputable websites that specialize in Apple laptop components and they offer replacement SSDs in various capacities.

You can’t just stick any SSD off the shelf of your local big box store into a MacBook Air. Nice machine, love the display, but the complete lack of upgradability is one of a few concerns raised about that model. Unless you have a new, 2018 MacBook Air, in which case Apple permanently soldered the storage. What Apple doesn’t mention is that the SSD in a MacBook Air can actually be replaced by the user, and it’s a relatively easy procedure. In addition, if it’s a mid-2012 model or earlier, the MacBook Air is on Apple’s “Vintage” list, meaning the company has discontinued support. Apple has always said the MacBook Air contains no user serviceable parts, so what do you do if the SSD in your laptop fails? What if you need more storage capacity? You can take it to an Apple Store for service, but that can be expensive and leave you without the machine for a few days. SSDs are far faster and tend to be longer lasting than traditional hard disk drives, but they are not infallible. Apple’s MacBook Air has always been a solid and reliable little laptop - even more so when the company ditched the hard drive that was in the original for solid state storage.

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