Is Twitpic Really Faster Than Posterous? Proper Testing

Someone had a moan today that the pics I was posting to Posterous were taking ages to load over 3G compared to pics posted on Twitpic.  Being the inquisitive type that I am, I decided to put the two sites to the test by uploading the same image to both sites at the same time.

My initial findings were that Twitpic loads about half a second faster on my rather nippy ADSL line in Safari 4.  The extra half a second seems to be a bit of DNS shuffling and redirecting that Posterous does before loading the actual page.

Try it for yourself:

Twitpic
Posterous (doesn’t exist anymore)

As far as image resizing goes, both sites resample the image for the web friendly preview and there’s little to choose between them in both quality and file size.

As for the code each page carries, The source for the Posterous page is around 24k and the Twitpic page around 8k.

As these results aren’t very conclusive, I went to [site no longer exists] to get more detailed reports for both sites.

The basic info on the amount of data each page contains is as follows:

The total size of the Twitpic page is 223740 bytes, which will load in 47.59 seconds on a 56Kbps modem.

The total size of the Posterous page is 208572 bytes, which will load in 46.37 seconds on a 56Kbps modem.

So as far as I can see, the main thing slowing Posterous down is the DNS reshuffling before the page itself loads.  There is also a possibility that the way the end user’s browser handles Javascript may affect the speed.