Social media users from all over the world, mainly Europe and the US, reported having problems with Instagram at about 14:00 GMT.
Residents of the US, UK, France, the Netherlands, Germany, and Serbia have encountered problems with the app. Issues with the social network have also been experienced by users in Russia, mainly in Moscow. Facebook users also experienced problems sharing photos, videos, and files.
The DownDetector website has shared a map showing the origins of most of the reports.
Users have taken to Twitter and other social platforms to complain about the malfunction.