I stumbled onto EOSInfo (Windows) – a utility that displays the shutter count for my Canon EOS 40D (and many others).

Mac users, try 40D Shutter Count.

Next, find your camera in the Camera Shutter Life Database and see where you stand. (On the Canon EOS 40D page, I’m entry #210 – 67,402.)

I don’t know if the survival estimations can be accurate with such a small sample. My hopes are that more people will submit their shutter counts to the database.

If you’re looking to buy a used Canon EOS DSLR camera, contact the seller and ask them to post screen shot (Windows 7, Mac OS X Leopard) with their shutter count.

How long will the shutter in your Canon EOS DSLR camera last? Look at the official webpage for your camera model under the Features tab. For the Canon EOS 40D:

Strong, rugged build quality: magnesium-alloy exterior, shutter durability-tested to 100,000 cycles, top speed 1/8000, top x-sync speed 1/250.

Fortunately, when your shutter dies, I’ve heard that $200 is the cost (from Canon) to replace the shutter.

When trying to pick a used camera body to buy, keep that number in mind, but understand that the shutter can go at any time. The best thing to do is have an emergency fund for shutter repair and/or a backup camera body.