How Long Does Time Machine Backup Take

Backups have been an essential tool to recover lost data. Data is even more critical when it comes to computers because we do not store as much data on smartphones as on computers. Every file and software data is crucial and must take periodic backups.

Apple provides a built-in software called Time Machine for Mac. It takes backups of your data and transfers them to an external storage device connected to your Mac. However, some issues with your backup could cause it to get stuck.

That is why you might wonder how long Time Machine backup takes. Let’s find out how to resolve it and the factors affecting it.

Why First Backups is Always Slow?

When you back up for the first time, Time Machine will have to copy every bit of data of your entire Mac. This will take more time. Depending on your data size, it could even take nearly 24 hours. You might think that Time Machine also keeps backing up after the first process, so why does it not take much time then?

The reason is that Time Machine only backs up changes you make to your files after the first backup. It will not back up all the data from scratch. This strategy makes it very fast to take a backup of all files.

Why is the Time Machine Stuck on a Backup?

There could be many underlying reasons for which you will face the said issue. These include:

  1. If your previous Time Machine backup got corrupted.
  2. Your anti-virus program has blacklisted Time Machine backups.
  3. The OS of your Mac is not up-to-date.
  4. You have not shut down your Mac properly.
  5. Your Time Machine has not been running for a while, and you have made many changes to your data. This will automatically take more time.
  6. You disconnected your disk or external storage device without ejecting.
  7. Your backup includes large files. You should back up those separately. Navigate to Systems Settings → Time Machine → Options to exclude any file from being backed up.
  8. If you use virtualisation on your Mac to run different OS, you will have multiple massive disk images. They will take more time, and the size will increase as your data in those virtual systems increases.
  9. The processing power and RAM also play an essential role in creating backups, especially the initial one.

How Can You Resolve the Issue of Time Machine Being Stucked?

1] Restart Your Mac

The best approach is to force-stop your Time Machine backup by navigating to Apple Menu → System Settings → General → Time Machine. After stopping the backup, restart your Mac.

2] Check Your Anti-Virus Program

Ensure that your anti-virus program is not scanning your Time Machine and the external storage device.

3] Ensure Latest macOS

Go to System Settings → General → Software Update and check for updates. If they are available, you should install them.

4] Disable Disk Throttling

Time Machine is designed to stay invisible. It does not affect the programs and tasks you are doing on your Mac, which tells macOS that it is unimportant and will limit its resources.

When you turn off disk throttling, Time Machine can access as many resources as it needs to perform large backups. To achieve this, follow the steps below.

  • Launch the Mac Terminal either via Spotlight search or the Finder. If you use Finder, go to Applications → Utilities folder.
  • Paste the following command in the terminal

sudo sysctl debug.lowpri_throttle_enabled=0

  • Hit return and type your admin password. When you type, the characters will be invisible, so ensure you type correctly. After typing the password, hit return again.
  • Time Machine will take back up with as many resources as it needs. After the backup process, you need to enable the disk throttling again. To do this, relaunch the Mac Terminal and paste the following command.

sudo sysctl debug.lowpri_throttle_enabled=1

Your External Storage Device Could be the Real Culprit

Time Machine copies the files on your Mac and stores them in a secondary location, your external storage device. The read-write speed of any portable external storage device highly depends on its USB port.

For instance, a device with USB 1.1 would only support a speed of around 2MB/s. Similarly, peripherals with USB 2.0 would support 30-60 MB/s speeds. The latest USB generations even support around 1.25GB/s. Ensure you are not using a peripheral with an older USB port.

Besides these, if you are using a Network-Attached Storage (NAS), delays will be added if you are several routers away from the NAS device. Try to minimise the number of routers between your Mac and the NAS. Or, connect the Mac with an Ethernet cable.

Bonus Tip

If your Mac supports Power Nap, you can use this feature to back up your data while your Mac is in sleep mode. With Power Nap, your Mac will wake up periodically to run some routines. You can even take backups. Navigate to System Preferences → Energy Saver → Enable Power Nap.


Time Machine is a great way to back up your Mac data and transfer it to a safe storage place. However, there could be many scenarios in which it takes longer than usual. You can use the above tips and tricks to resolve this and understand why it happens.