My new Macbook Pro with 512GB SSD only shows 500GB! Why?

Read here to understand why: How iOS and macOS report storage capacity - Apple Support

iOS and macOS use the decimal system

The operating system of your iPhone, iPad, iPod touch, and Mac reports storage capacity using the decimal system (base 10), which calculates 1GB as 1 billion bytes. This is the same measurement system used on the product packaging and specifications.

iOS 10 and earlier, Mac OS X Leopard and earlier, Microsoft Windows, and watchOS use the binary system (base 2), which calculates 1GB as 1,073,741,824 bytes. This difference between the decimal and binary systems of measurement is why the reported storage capacity differs from the storage capacity on the product packaging or specifications.

What's the model number of the drive? You could have a drive that's actually 500 GB. Did you look in Disk Utility for the model name/number?

Mine shows up at the top as "SanDisk SDSSDH3512G Media" with 512.11 GB. Underneath it in the tree is Container disk1 and my drive name as 511.9 GB. It also shows up as 511.9 GB with Get Info on the boot partition.

All of the Retina MBPs seem to come only with 128/256/512/1TB where it's a base 2 value for the capacity. The only thing I can think of is that there can be variances where it might be a little bit more or less than the rated capacity, but not off by that much. Sometimes bad blocks can be "quarantined", which lowers the capacity.

I looked up the drive info, and that's from a 2015 model. Is it a new machine or just "new to you"?

A few GB is used for a hidden recovery partition.

Then there's the macOS system files which take a couple more GB.

That's supposed to be 512 GB. I did see this claiming it was 500, but it's different that other benchmark sites saying it's 512 GB.

http://ssd.userbenchmark.com/SpeedTest/25611/APPLE-SSD-SM0512G

babowa wrote:

I am curious: if yours is a 2015 and you buy it in 2018, how can you be sure that you are getting a brand new computer? Was the box still factory sealed?

Adorama is an Apple Authorized Reseller though. Here's a mid-2015:

https://www.adorama.com/acmjlq2lla.html

I don't know exactly how they do it. I haven't really seen too many old models still being sold although I've seen it occasionally. Amazon does it, but they will make it clear that it's not a current model. I remember when the latest one would come out, CompUSA (RIP) would have the old model at a discount.

My big concern about a device that old is that it's been sitting in storage for a while, and the battery might suffer from self-discharge. Perhaps not totally gone, but where there might be some loss of capacity as a result of deep discharge.

It may also be a pain to try to register it for the warranty because Apple starts the warranty when it ships the product to the reseller, so on anything that old, the warranty would long be expired. I had to deal with that once. In order to "revive" the warranty, you have to buy it from an authorized reseller and I had to send in my purchase receipt and ask the retailer to send in something as well (certifying that they sold it to me). Maybe they've changed that process, but at the time, it was a pain.

babowa wrote:

It may also be a pain to try to register it for the warranty because Apple starts the warranty when it ships the product to the reseller, so on anything that old, the warranty would long be expired. I had to deal with that once. In order to "revive" the warranty, you have to buy it from an authorized reseller and I had to send in my purchase receipt and ask the retailer to send in something as well (certifying that they sold it to me). Maybe they've changed that process, but at the time, it was a pain.

The warranty is legally supposed to start at the date of retail sale though. I’ve bought Apple products where Apple said the start of the warranty was approximately starting the date I activated it. I would need a receipt though if it’s close to the end of the period. I had an accessory warranty claim, and using the online coverage check at and Apple Store for the serial number was enough.

babowa wrote:

The warranty is legally supposed to start at the date of retail sale though

It does - Apple sells it to the reseller = warranty is activated.

But legally a consumer warranty starts at the date of the retail sale to an end user. I do understand the issue with gray market sales, but that's clearly where the "retail sale" is before it gets to the end user.

That shouldn't be an issue with a Retina MBP.

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