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Shutter Count vs File Number (IMG_0001)

The single most common misunderstanding in used-camera buying — and the easiest one for dishonest sellers to exploit.

They are not the same thing. The file number (IMG_0001, IMG_9842…) is just a filename counter — it resets with a formatted card or a menu option. The shutter count (actuations) is stored in the camera’s protected internal memory and never resets through any menu.

How sellers (accidentally or not) mislead with file numbers

“Only 2,000 shots — see, IMG_2000!” — meaningless. Format the card, reset file numbering in the menu, and any 300,000-click body shows IMG_0001.
File numbers can also run higher than the count — insert a card from another camera and numbering continues from the highest number found.
The only trustworthy number comes from reading the camera over USB with a tool like EOS Digital Info — free download here.

The 10-second rule for buyers

If a listing justifies its price with a filename (“low IMG number”), treat the count as unknown until verified over USB. Ask the seller to read it in front of you — refusal tells you everything.

Buying a used Canon?

Check the shutter count before you pay — then buy where used gear is graded and returnable:

Browse used Canon at KEH Browse used Canon at MPB Used Canon DSLRs on eBay

Disclosure: these are affiliate links — we may earn a commission at no extra cost to you.

Frequently asked questions

My camera shows IMG_9999. Is the shutter worn out?
Not necessarily — that’s just the filename counter rolling over. Read the true actuation count over USB to know the real number.

Can formatting the card reset the shutter count?
No. Formatting only affects the card and the filename counter. The internal actuation count is untouched.

Why doesn’t Canon just show the count in the menu?
Canon treats it as service data and never exposed it in consumer firmware — which is exactly why third-party tools exist.