What is a sparsebundle? Your old Time Machine backup explained

Published: 2026-10-27 · Capsule Bridge

Short answer: a sparsebundle is a disk image that Time Machine creates on a network disk. It looks like a single file in Finder, but it is really a folder of many small pieces that together act as a whole backup disk. When Time Machine used a Time Capsule, your Mac's backup lived inside one.

Why a bundle and not normal files?

Time Machine needs a disk it can format and control. A network disk cannot be formatted by the Mac, so Time Machine makes a disk image on the network disk and treats that image as its backup disk. The image is split into many small pieces called bands. This lets the backup grow gradually and lets a backup be updated without rewriting one huge file.

Why is it so large?

It holds every hourly, daily and weekly snapshot Time Machine kept, so it can be several hundred gigabytes. On one 2013 Time Capsule we tested, the backup of a single MacBook Pro was 366 GB, more than half of all the data on the disk.

How do you keep it safe?

• Do not open or edit its inside by hand. Moving or deleting bands can corrupt it.
• Copy the whole bundle. Copy the .sparsebundle item as one unit to a modern drive. It can take hours.
• Keep the original until the copy is checked. Open the copy on a Mac and see that it mounts.
• Decide if you still need it. If the Mac it belonged to is gone, the backup is only useful for recovering old files. Many people keep a copy and stop there.

Can you still use it?

Yes. Once the bundle is on a normal drive, a Mac can open it like a disk image and let you browse the old files. If it does not mount, keep the copy and try on a Mac running an older macOS.

Related: how to get your files off a Time Capsule.