It's not just you: Google Photos is down and photo backups are, too

Google Photos website and automatic photo backups are on the
fritz right now.

Google
Photos
is one of the unsung heroes of the Google ecosystem, and
its free, fast photo backups are a godsend for shutterbugs and
screenshot over-sharers like me. Unfortunately, it seems they’re
not working tonight for a large number of users around the
world.

If you open the Google
Photos website
right now, you either get a totally blank photo
feed or the 503 error seen on the right. If you snap any new photos
on your phone that need to be backed up in the
Google Photos app
, you’ll get a looping message at the top of
the Photos feed that it is “Getting ready to back up”.

The outage seems to have started roughly an hour ago — around
5:30 PM ET — but it seems to be impacting users worldwide. If you
were wondering why your photos weren’t backing up — or why you
can’t download those screenshots you need for a new blogpost —
you now have your answer. We don’t know how long things are going
to be down, but we’ll let you know as soon as it comes back!

As a friendly reminder in this time of need, if you need to
access photos you already backed up to the service while the main
Google Photos site is down, remember that there’s a Google Photos
folder in your Google Drive
where all your photos are files away by year and month.

Source: FS – Android
It's not just you: Google Photos is down and photo backups are, too