The amount of ink used by a laser-class or inkjet printer depends on the type of document printed. A vendor's estimate of ink cost is typically based on a business document with a rather low 3 to 5% coverage. If you print full pages, the estimates are not going to be accurate. As you can see from the sample pages below, the costs can vary greatly.
Ink Coverage Percentages
Although the cost-per-page estimates for these Tektronix printers are in 1999 U.S. dollars, the comparisons are still valid. The more graphics and color, the higher the cost. The Phaser 840, a solid ink printer, was the least costly. The 740 and 780 were laser printers. Tektronix color printers were later acquired by Xerox. (Image courtesy of Tektronix, Inc.)