just figured this out and i’m super excited~~~
So you know when you’re reading through general tumblr tags and the url looks like this (this is the url going one page back in that tag, from today, 3/30/2013):
Turns out the number at the end means something, and can be changed so you can go to the general tumblr tags for any date you specify.
For instance, if I want to go the one direction tag as of January 1, 2012, I would go to http://www.timestampgenerator.com, enter the date, and this number would be generated:
I replace the number in the above url with this number, to get this url:
And now I can see everything people tagged with “one direction” around the time of January 1, 2012. If you care about the exact timing, remember to specify your time zone (in GMT +/-x) and take note of the time zone that shows up by default on posts in dashboard mode (in xkit, you can set the time zone to your own with the ‘timestamp’ extension, other scripts and extensions may work differently).
What this number means (roughly) is the number of seconds that have passed since midnight January 1, 1970, GMT. It is also called Unix time and is a standard way of calculating timestamps for anything that is unix-based.
Since a lot of people are finding this post from google, I thought I’d add this now that I’ve figured it out: how to go back in time on your tumblr dashboard. The first thing you need to know is what a post id is. A post id is the number that is part of every tumblr post url, and is (I assume) a count of the total number of posts which have been made on tumblr ever at the time the post was made.
For this post, the post id is 46716818218.
One thing that is important to know about tumblr is that while you CAN change the date shown for a post on your tumblr theme, you CANNOT change the post id - it is static even if you edit everything else about the post (even if you change your url, the post id will be the same, even if you delete the text after the post id in the url, your browser will still find the post). This also means if you create a post today, tag it and backdate it to a date a year ago, it won’t show up in tags for a year ago (because posts in tags are organized by post id).
If I wanted to see what was on my dashboard at the time I originally made this post, I would enter this url:
If I want to go to my dashboard for a date I don’t have a post for, I would first use the method described above to get a timestamp for that date. Then, I would go to a tumblr tag that is at least reasonably popular, pick a post in that tag from time of the timestamp I’ve chosen, and use that post’s post id in my dashboard url.