My backup is saying it will take 17 hrs. It’s been “backing up” for 8 hrs already and the blue bar is not even as far as the “B” in “Backing up…”. The last time I tried backing up it got up to over “20 hours remaining”. What the heck is going on?

Hi boleypa,

Though you have not indicated what you're backing up or to where, you did create your post from the support article What does iCloud back up? in the iPhone Communities page so that will be assumed. If not the case, replying with additional details may help future replies.

From the support article How to back up your iPhone or iPad with iCloud the steps to back up to iCloud are:

1. "Connect your device to a Wi-Fi network.
2. Go to Settings > [your name], and tap iCloud.
3. Tap iCloud Backup.
4. Tap Back Up Now. Stay connected to your Wi-Fi network until the process ends. Under Back Up Now, you'll see the date and time of your last backup. If you get an alert that you don't have enough iCloud storage space to complete the backup, follow the onscreen steps to upgrade your iCloud storage."

The amount of time needed to create a backup will depend on the size of the data to be backed up and the speed of your Wi-Fi connection. A first backup will take longer than subsequent backups. Further information can be found in If you can't back up to iCloud:

"If your iCloud backup is taking longer than expected to complete

1. In iOS or iPadOS, go to Settings > Wi-Fi. Check that you're connected to Wi-Fi. 
2. Check your upload speed.
3. Leave your device connected to power and Wi-Fi for 24 hours. If your backup still isn't done, archive important data then contact Apple Support. "

Regards.

Hi boleypa,

We appreciate you providing us with these additional details.

There are multiple factors that may affect the speed of the completion of a backup.

One factor is the amount of data that will be included in the backup.

Another factor is the speed and stability of your internet connection.

If possible, please connect to a known-good Wi-Fi network. A Wi-Fi network is likely faster and more stable than cellular data.

If the issue persists after trying a known-good Wi-Fi network, please use the link below so we can take a closer look into the issue.

Get Support

Take care!