?If you've ever been in the market for an ink jet printer or ink cartridge, you've probably come across the term "expected print yield" in your search. This term is used by manufacturers to refer to the average number of pages consumers can expect to get out of a cartridge. Most ink printer manufacturers list the expected print yield along with other saleable features such as print quality, speed, and ease of use so that purchasers can estimate how much ink they can expect to use with that model. Consumers can usually find the print yield information on the manufacturer's webpage featuring their printer's specifications. Depending on the manufacturer, you may find specifications for both black and color inks. Sites for higher-end printers may feature yield numbers for specific colors as well. Most printer manufacturers base their print yields on standards set by the International Organization for Standardization (ISO), the largest developer and publisher of international standards. In December, 2006, the ISO approved standards for both ink (ISO/IEC 24711) and color toner (ISO/IEC 19798) cartridge yield measurements. Before this standardization, printer manufacturers used various and sometimes conflicting methodologies, which made it hard for purchasers to accurately compare models based on their print yields. Manufacturers often express their average yields in expected pages. For example, Hewlett Packard (HP) lists its 96 Black Inkjet Print Cartridge as yielding 860 standard pages. HP calculates their print yield numbers on a suite of five pages they print consecutively until the cartridge reaches its end of life, which is when the cartridge ink begins to fade or when the printer automatically stops because of out-of-ink detection. The test requires a minimum of three cartridges of each cartridge type run through three printers to account for any variations. For their color cartridges, HP publishes a 3-color composite page yield that offers an average for the colors Cyan, Magenta and Yellow. For HP photo cartridge yields, the manufacturer uses its own standard because there is no industry standardization to date. The test entails printing a continuous set of 10 4x6 inch photos until the cartridge reaches its end of life. Lexmark also abides by ISO standards, using nine print cartridges in their print yield testing until they reach the end of life. Their test suite consists of four typical customer pages and one diagnostic page printed using the most recent version of a PDF reader. Like HP, Lexmark tests three cartridges on three different printers to avoid bias from printer variability. Their calculation is presented as Page Yield = Average Page Yield - (1.86 * (std dev of page yield/3)). Lexmark states on its site that it will publish actual page yields for all future products. Using the same ISO standards, Epson lists yields for its NX510 and NX515 cartridges as 245 pages for its standard-capacity black color and 340 pages per color for their standard colors Cyan, Magenta and Yellow. For their higher-capacity cartridges, a consumer should expect 410 pages for a black-ink cartridge and 525 pages per color for an average yield of Cyan, Magenta and Yellow. Their extra high-capacity yield for black is 900 pages. Print yields allow purchasers to shop smarter when buying printer cartridges. Consumers should check to see if the manufacturer lists the expected end-life of a cartridge. After a certain period, cartridge ink cakes up and dries, making it unusable. This can be a waste of money if the printer is not used regularly. To offset this problem, some printer cartridges include chips to prevent use after a certain date. At this time, consumers can only get printer cartridge yields from manufacturers, so you should compare the information given at various websites to make sure you are getting an economical as well as quality cartridge purchase.John Pickering is the owner of EezyTrade.co.uk, an online retailer of new and refilled printer ink cartridges for Brother, HP, Canon, Epson, Lexmark and Xerox printers. Visit online today and begin saving.