It is becoming increasingly common to store and share files online, and there are a large number of websites that offer this service. Whether they are business documents, videos or images, once the files have been uploaded from your computer to the online storage service of your choice, your ability to share these files depends on the availability (uptime) of the service you are using.

Many of these storage services also offer paid options, often as online storage solutions for companies and advanced users. That makes it even more important that they have a very high availability. After all, a file storage solution is useless if you cannot access your files.

Ideally these services would be up and running and fully available 100% of the time so you can always access your files. However, this is not an ideal world and there are a lot of technical challenges for these services to provide a reliable website, including potential problems with servers and networks. This is not a unique problem to online storage services, but to all websites and services on the web.

The facts after 3 months of uptime monitoring

We collected a mixed list of online storage services, from well-known players like MegaUpload (the 15th most popular website in the world according to Alexa.com), SendSpace, YouSendIt and DropSend, etc, to various smaller alternatives. These were then monitored for three months, June through August. You can see the total downtime per website below for this three-month period in the diagram below:

As you can see from the diagram, the availability of these services vary enormously. The service with the worst uptime has 796 times more downtime than the service with the least downtime.

It is also clear, especially when looking at the monthly downtime numbers (available in the table below) that the difference from month to month can be significant. An excellent example is MyTempDir which had very good uptime both in June and July but ran into serious problems in August when their service was unavailable for hours on end, in one case 22 hours in just one day.

There is of course more to a service than just availability. Usability, support, download and upload speed, storage space, and many other factors should be considered when choosing an online storage solution, and also whether it is intended for private or corporate use. The numbers we provided in this survey are just one thing to factor in when (and if) you make a decision.

Survey data

For a monthly breakdown, here is a table with the monitoring results. The columns show downtime, i.e. when a website did not respond or gave an error.