Instagram, Facebook and WhatsApp down: How long is major outage likely to last?

Previous major outage lasted almost a day

Facebook, Instagram and WhatsApp have all stopped working properly. And it's not clear when they will start again.

All three of the apps simultaneously started to suffer for problems. The issues have been ongoing for hours, and could last for much longer.

Unusually, the services are not simply down, or not working for some users. Instead, specific parts of the apps have stopped working: both WhatsApp and Facebook are struggling to show photos, for instance, and other parts of them are showing error messages.

With such outages, it is impossible to know how long each lasts, since the services opt not to be very transparent about the problems or what could be caused. Often, they are fixed within minutes, with issues only being a blip. Most often they are fixed in less than an hour, with Facebook like other sites rushing to fix them because even a short outage can affected tens of millions of users and cost vast amounts of money.

But sometimes they do last much longer.

In March, Facebook was hit by its biggest outage ever, which took down Instagram and WhatsApp at the same time. Since those three apps are among the biggest in the world, it also meant that the outage was probably the biggest ever seen globally.

It lasted almost a full day: from the early morning local pacific time until the same evening, and with service only returning in an unreliable way.

It never said exactly what had happened. But it did post a tweet that aimed to explain some of the problem, and suggested that it had been an error.

"Yesterday, as a result of a server configuration change, many people had trouble accessing our apps and services," it wrote. "We've now resolved the issues and our systems are recovering. We’re very sorry for the inconvenience and appreciate everyone’s patience." Such an explanation reveals little about what actually went wrong, but could offer a hint at how such problems last for so long.

Major services like Facebook, Instagram and WhatsApp are so big that turning them around can take a long time: if traffic is being sent to the wrong place, for instance, then millions of people could follow that and overwhelm the service, a problem that could take some time to fix. A web service like Facebook actually exists in various servers across the world, some of which are not necessarily actually controlled by Facebook – so a change could take some time to be reflected right across the web.

That means that even when a problem is fixed, it might not be fixed for everyone. And the bigger the problem, as well as the bigger the website, the longer all of that will sometimes take.