Ah, the eternal question. Unfortunately, it is a question with no answer. Every manufacturer makes different sets of cartridges with different amounts of ink in them and they all usually don’t even specify page counts anymore. When it comes to laser cartridges, you will find that most manufacturers will estimate the numbers of pages you are going to get. With laser cartridges it’s easier to guess because people use them mostly for documents and since they last a few thousand pages, it’s easier to estimate since your margin of error has gone up.

The reason why it is even impossible to guess how many pages someone will get from their cartridge is because it all depends on the type of printing they do. Someone could be using a cartridge to only print text documents, and someone could be using it to print 8 x 10s - obviously there is going to be a big difference between the life of the cartridge for these two types of use. With so many printers having photo cartridges now, it’s also difficult to tell which cartridges are actually being used and when.

The other thing that makes this question difficult is that, for the most part, printer manufacturers do not advertise how much ink is in their cartridges. Basically, only HP will tell you the milliliter content of their cartridges. You can check the packages and search around on their websites, but generally that information is impossible to find or nonexistent.

In the old days, HP estimated that their 51645A cartridge could yield approximately 833 pages. These page yield estimates are based on 5% coverage, which unfortunately means that they are way too high because really nothing takes up only 5% of a page. Also, this cartridge is giant compared to HP’s current cartridges. The 45 black contains 42 ml of ink, while the HP 96 contains 21 ml and the HP 94 contains only 11 ml. The following information on HP’s site basically sums everything up:

HP 45 - 42 ml of ink, 833 page yield.
HP 96 - 21 ml of ink, 800 page yield.

So, even when they are giving us information, it is wrong in some way. With inkjet printers, there really is no guessing and all you can really do is watch your ink monitor level.

The one thing you can do to ease this situation is to print in Draft mode. Honestly, how many of your prints ever leave your house? If you aren’t printing photos and aren’t printing something that you plan to give/show to someone, go to your printer preferences and select FastDraft or whatever your printer calls it. Your prints will be done in half the time and you won’t waste ink. This is especially helpful when printing out web pages, since they usually contain lots of colors or images.