Well, the data from my previous catchall experiment is in. The aim was to reduce the level of email spam I was getting. I recorded the number of emails in my Gmail spam folder which reflects the number of spams received in the last 30 days (after which spams are deleted). Data was sampled over a one month period and 23 data points collected. I switched off the catchall address a third of the way into the experiment, so emails to nonexistent accounts are bounced instead of silently accepted. I hoped the spambots would take this as a sign to give up on those addresses. I’m also told that when an email is bounced the full email is not downloaded by the receiving server, so this should reduce email traffic slightly (not that I’m close to my hosts limit).

I would have done a longer, more thorough experiment but there needs to be an easier way to collect the data (using Gmail API perhaps?) Anyway the results are below.

Conclusions? Well the graph would seem to indicate spam levels decreased somewhat linearly after the switch, and they stayed around a 450 average in the following months… until a couple of days ago when the amount skyrocketed to 780! Maybe I was just hit by a very eager spambot, who knows. But after that I’m reluctant to draw any conclusions at all from the experiment. It’s not like these spam levels are a problem; Gmail kicks total spambot arse!