The cloud storage war is heating up. Dropbox is getting more and more competition, and now Google has joined the fray with Google Drive. We’re not going to compare features in this article, but rather test something we can actually measure. And since we here at Pingdom do site monitoring we have focused on how these services compare in terms of performance and reliability.

To make this survey even more interesting, we also added two other file hosting services: Microsoft’s SkyDrive and Box.com. They should give us some additional perspective.

To monitor reliability and performance, in this specific case we thought their homepages were less important than the actual file hosting they offer, so that is what we focused on. We uploaded the same identical file to the four services, a small PNG image, and made it publicly available so we could monitor it.

Service reliability

First we should get the reliability question out of the way. Our monitoring indicates that all of these services offer great availability, with some minor differences.

During the 30 days of this survey, the only service that had zero downtime was Box.com. However, Google Drive was very close to getting a perfect score here as well, with just 1 minute of downtime. This means that both had 100.00% uptime (that minute for Google is too short a time period to show up unless you add more decimal points).

Box.com and Google Drive should be applauded for having no or close to no downtime over the time period of this survey.

Dropbox had a perfect record until the very last day of this survey (yesterday) when it had a single 13-minute outage, reporting the service unavailable when we accessed the file. That still puts it at a very respectable 99.97% uptime. You could say that bad timing kept Dropbox from getting a perfect score in this survey.

Microsoft’s SkyDrive was having some issues at the beginning of this survey, with multiple short outages of 1-2 minutes each. This was also noticeable from a performance standpoint, which you can read more about further down in this article. That said, with just a total of 15 minutes of downtime it can hardly be called a disaster. When rounded off, this puts SkyDrive at 99.97% uptime.

So, in short, over 30 days this is the score in terms of file availability:

1. Box.com – No downtime, 100.00% uptime
2. Google Drive – 1 minute of downtime, 100.00% uptime
3. Dropbox – 13 minutes of downtime, 99.97% uptime
4. SkyDrive – 15 minutes of downtime, 99.97% uptime

In our opinion, the amount of downtime we saw was fully acceptable. No service will have perfect availability in the long run. The important thing is that outages are dealt with swiftly and don’t happen too often.

Tests were performed once per minute, and downtime was always verified from two different monitoring locations to avoid false positives (the Pingdom monitoring service does this automagically).

Performance

It could be argued that since files hosted on these services aren’t really meant for performance-sensitive resources, only sharing, performance isn’t as important here as reliability. We think both matters, for the simple reason of user convenience, for the same reason we prefer a fast website to a slow one.

The URL we monitored was the one you get from the various services for publicly accessing a file. Worth noting is that Google Drive, SkyDrive and Box.com all add a small wrapper page to a shared file, which of course adds a bit of overhead to load times.

Larger version of the chart.

We started the survey before Dropbox announced its decision to drop support for public folders for new accounts, instead adopting an approach more similar that used by Google Drive et al. This survey used Dropbox’s Public Folders feature, so it’s quite possible that shared files will have some additional overhead above what you see here, but we haven’t had time to test that yet.

So who wins this? Google Drive and Dropbox are clearly pretty close, and don’t forget that Google also includes that wrapper page for the file so that’s a certain amount of overhead. They both offer significantly better performance than both SkyDrive and Box.com here.

An interesting trend is that all of these services, to different extents, have better performance when accessed from locations in North America compared to Europe. Google has the most geographically even service in terms of performance, with Dropbox a close second.

An additional note about SkyDrive

SkyDrive was clearly having some issues when we started this survey, which affected its performance results in this survey. That is also when it clocked in the downtime we detected. You can clearly see how performance changed over the course of this survey.

Shown above is the load time of the image and its wrapper page on SkyDrive. The graph is from the My Pingdom control panel.

Final words, and a verdict

It’s interesting to note how many cloud storage services there are out there, and so many that provide storage for free (all four in this survey do this). There clearly isn’t a lack of options.

That said, Dropbox has a huge fan base, and not without reason. We use Dropbox extensively here at Pingdom for various purposes, and think it’s a great tool which offers a very good user experience.

However, this survey was all about numbers. To answer the initial question, what happens when you compare the performance and reliability of Dropbox and Google Drive? The answer is that they are close enough that the differences don’t really matter in this case. Use the one you think gives you the best user experience. Or why not use both?

Top right image via Shutterstock.