Five percent paper coverage has become the industry-standard for measuring ink cartridge yields. HP, for example, rates its 45a cartridge as being good for 833 pages at five percent coverage before the cartridge runs dry. But is five percent a realistic number? Are real-life users likely to print documents with such a low coverage? To find out, I performed a page coverage analysis on a variety of documents.

What is Page Yield?
HP, Epson and most printer manufacturers publish a "page yield rating" for most of their cartridges. The page yield rating tells you the number of pages you can expect before the cartridge runs dry. The page yield rating is usually based on five percent page coverage.

What is Page Coverage?
Page Coverage is the percentage of a printed document that is covered with ink. For a black and white document, a nine percent page coverage means that nine percent of the page is black, the remaining 91 percent white.

Page coverage: 5.95%

This is what I consider to be a typical document - 12 point Times Roman with one-inch margins. It has a page coverage of 5.95 percent - 19 percent greater than the five percent standard. Remember, greater page coverage means more ink usage. So if you print nothing but documents that look exactly like this, you can expect about 675 pages from a 45a cartridge - 19 percent less than the 833 pages HP is claiming.

Page coverage: 9.16%

Add a six point border and coverage increases to 9.16 percent, while page yield drops to just 455 pages. That's a big drop from just adding a border!

Page coverage: 8.32%

Looking at this unfortunately familiar document, I was sure it was going to use more ink than the bordered text document above. It looks blacker to my eyes. But nope, I was wrong. 8.32 percent coverage, 502 pages yield. Perhaps I was just biased because I hate the IRS!

Page coverage: 21.79%

The page above has an ink coverage of 21.79 percent leading to only 191 pages before the 45a cartridge runs dry - 77 percent below the 833 page rating. If I were printing this document, Id start at page 2 to avoid the ink-hungry (and essentially useless) cover.

Page coverage: 4.31%

So what kinds of documents actually have a page coverage of five percent or less? Well, take the text document at the top and increase the line spacing to 1.5, and you will obviously use less ink per page. You wont save any ink, of course, as the text will wrap onto the next page. But that's basically what you have to do to get below five percent. I tried changing fonts alone and wasn't able to come up with any realistic-looking pages that used less than five percent.

My conclusion: Five percent is not realistic for most people. The page yield you actually get from a cartridge will probably be at least 20 percent lower than the rating, and it may be much lower than that, depending on the type of documents you print.

Inkfarm uses the five percent standard when rating our remanufactured and compatible cartridges. We do this so you can do an apples-to-apples comparison of our products with OEM cartridges and those from other vendors. Just know that your actual page yield will probably be somewhat lower than the rating, and will depend on the type of documents you are printing.