When you buying pretty much any product, it's important to know exactly what it is you're buying and what you're getting for your money. When purchasing your printer cartridges is just as important to do the same.
Practically all cartridges now come with a page yield on the packaging to help you know what to expect when it comes to printing. But what does page yield even mean and how accurate is it?
The page yield is an estimated figure of how many pages you should get from your cartridge. HP and other industry specialists are involved in developing the standards that are used to measure the page yield and they do so extremely accurately.
They test the yield by printing pages with approximately 20% overall coverage (5% of each colour) on the page. As you can see the pages below that they use are full documents (albeit ugly documents) of black and colour.
Even with these test pages in front of us its still hard to understand exactly how much you will be able to print with your cartridge. Have a look at the visualization below, it shows an approximate coverage of 5% black text:
This shows that a pretty much regular document written in a regular size 11px Arial font covers just over half the page. In my personal opinion, you are more likely to print a document like the latter compared to the first two examples HP provide. If you were to print just photos then you would definitely not get anything near the page yield specified.
All this information and more is available on the HP website, if you fancy doing a bit more reading on the topic then feel free to do so. Just remember to take into account that although HP do their very best to provide an accurate estimate, the page yield is not exact and it depends on what you print.