I am thinking of buying a Time Capsule with a small hard drive and upgrading the drive to something larger. There is ample documentation on the web as to how to do it, but I am having a hard time finding any details as to what the upper limits of drive size are. It's especially confusing since there are four generations of Time Capsule, and each one may have a different upper limit. So, what is the upper limit of each? And, if you only know the answer to one specific one, that would be great, too.

  • 1
    It will be interesting to hear what size drives people have placed internally once they don't care about warranty coverage. Most I know that want more than 3 TB of Time Machine storage get a Synology NAS unless they just want more space and are OK connecting several 3 TB drives (or larger) to the USB port via a hub.
    – bmike
    Jan 14, 2013 at 19:07

3 Answers 3


Nobody seems to know what the official drive size limits are, but I just connected an 18TB hardware RAID to a 1st generation Time Capsule, and it works. To duplicate my setup:

Configure a 4-drive hardware RAID using this enclosure:


(I used four 6TB drives and set it up as a RAID 5)

Connect the RAID enclosure to the SATA connector on the Time Capsule's logic board using this cable:


This Time Capsule has pretty much been gutted over the years, so the only thing left is the logic board itself. It's powered by a 2A 5VDC external brick, WiFi and routing are disabled. It's just a hack NAS at this point...but it handles an 18TB drive.

  • 1
    FWIW, when formatting that RAID prior to initial connection to the Time Capsule, you need to make it a single non-journaled HFS+ volume. To do this, use "diskutil eraseDisk HFS+ RAID_Volume /dev/diskX" where X is the device number for the drive, found in Disk Utility. The TC will repartition the drive into journaled HFS+ volumes, but for some reason it has to start out as a single non-journaled HFS+ volume.
    – JLG
    Apr 26, 2020 at 20:47

I’m running a 4th gen. A1409 Time Capsule, originally equipped with a 2 TB drive. I replaced that with a 4 TB WD Green (iirc) with no problems so far.


Time Capsule 802.11n (1st generation) introduced Jan 2008 is working with 2TB drive. I did not try larger (yet).

Not the answer you're looking for? Browse other questions tagged .