How many times do you typically use a DE blade ?

I usually use each blade 2-3 times, but when I realized I was stocking up much faster than I was using them, I started tossing them after just one use.

Usually 2 times but some of the blades could do over 5 shaves

I generally use a blade twice.  Considering the cost of a DE blade, I choose results over price.

Best Vintage - between 5&7
Newer - 1&2

No more than a week

5-6 shaves with one razor used.

Usually 2-3 times, depend on both razors and blade.

Definitely depends on the blade, the razor and the face prep.
In general, I get from 2 (Feather DE) to 9 (Wizamet) shaves per blade in a DE safety razor.
One of my latest razors is the Focus Slim AL barber razor that uses 1/2 DE blades and so far, I am getting twice the number of shaves (and counting) as with a safety razor.

Well, I am learning something. As many of you know, I have been using a Pearl SE razor with half DE Silvermax (EuroMax) blades. I pretty much only use it as a clean up razor after a double pass SR shave so the blade doesn't get much abuse. It seems to last forever in this role......but.........

It is getting duller. It still cuts but I am now going to a fourth pass in the final orthogonal direction to get to BBS. I think that I am probably also using more pressure, in fact I am sure of it, and for the first time in probably a decade an old nemesis has surfaced.........ingrown hairs! I got one on my neck (used to get one all the time with the Gillette Track II) and my cheek.

So, the moral of the story is don't try to stretch out the life of the blade even if you can still get a close shave with it. It will inevitably lead to using more pressure and doing more passes, and for me that leads to ingrown hairs, even if there is otherwise no serious irritation.

Don't be that guy (i.e. me!)