This calculator shows you the number ways that a search can match your photo's keywords. For example, if your photo has 10 keywords and the user searches with a 3 word-phrase, there are 120 possible ways they can be matched.
This example relates to my article Keywording Photographic Images for Online Stock Agencies.
Example: for 25 keywords and 3 search terms there are 2300 unique hit combinations. (Translation: there are 2300 different ways a 3-word search can find an image with 25 keywords.)
Try 50 or 100 keywords with a 3-word search and see how the number of possible hits dramatically increases.
Try 99 keywords and 3 search words. Now try 100 keywords with 3 search words. Notice that for 1% more effort you get nearly 4% more chance of being found!
Most searchers start by entering just one word, for example "boats" in the stock agency's search box. But they quickly learn that the results they get from doing this are too general. They move on to more complicated searches like "boats tropical sunset" (3 words). If that doesn't help, they may try even more complicated searches like "boats tropical sunset waves people" (5 words).
Let's say you have been really lazy and put only 5 keywords to your image. See how many combinations of hits are possible with 5 keywords and a 5 word search. (The answer is obvious, if you think about it.)
Now compare that with your more industrious colleague who has a similar image but has indexed his image at his agency with 20 keywords. How many combinations of hits are possible for him? Yes, that's right, he is 15,504 times more likely to be found by our 5-word searcher that you are! Now stop drinking coffee and start learning about keywording images fast!