re-done 4/09                                  

Ever wondered what the cost is of printing your own stuff or the cost of the ink?

Many articles have been written about inkjet cartridge yields and how to measure it. The problem with these articles are, that none of them will tell you how much a square inch of printed matter cost. The information below is based on the manufacturers estimated number of fully printed pages per cartridge. In  the data below, I used the expected page yield per cartridge as listed by Epson the manufacturer of the ink cartridges I use. Every ink cartridge manufacturer lists cartridge yields in one form or another but the most common is the number of fully printed pages yield per cartridge. It is also assumed, that these yields are obtained through continuous testing to avoid ink waste through nozzle cleaning and internal/external ink coagulation and drying. Therefore, to establish a precise ink yield per cubic measuring unit is near impossible. But, we do want to know (to some extend) what the cost of our prints are otherwise we can not price them with any certainty.  If you have a printer other than an Epson, the manufacture of the cartridge you use should have the cartridge yield available. If not, call the respective manufacturers tech support and ask for it.  I page yields are not obtainable, most inks have the same viscosity and inkjet technology being about the same as it is, use the page yields used in the examples.  As for the retail cost, the calculations below are based on the suggested retail price of the manufacturer however, there are many suppliers that sell OM cartridges at discounted prices bringing down the cost per square inch significantly.

If one sends his images to a printing establishment, we know in advance the cost of a given print size. When you make your own prints however, this information appears to get lost in the shuffle so, I decided to try to calculate the cost of one square inch of printed matter on a good piece of printing stock using an Epson 2200 and the Epson R1800, two printers I currently use. The 2200 printer has seven ink cartridges and the R1800 has eight. Calculating the average ink use per cartridge when multiple colors are being used, is just about an impossible task however, know that one square inch of printed stock cost "X" amount is enough to calculate your print cost. The calculations below are based on border to border printing therefore, for prints that have white borders, subtract the calculated border area from the total square inch printed area.

Example, an 8 x 10 printed on an 8 ½ X 11 stock calculates as follows; Area of 8 ½ x 11 stock is 8.5 x 11 = 93.5 inch², the area of the printed surface is 8 x 10 = 80 inch², Area of unprinted border is 93.5 - 80 = 13.5 inch².

All estimates are base on Epson catalogue listed product prices.

Epson 2200, known data,

Calculated data,

• Cost of one square inch of Epson Premium Luster paper = (35 / 50) / (8.5 x 11) = $ 0.0075
• Cost of one square inch of Epson Premium Luster paper = (115 / 50) / (13x19) = $ 0.0093.
• Average cost of one square inch of Luster paper = .0075 + .0093 / 2 = $ 0.0084
• Page yields @ 1440 DPI @ 5% = 440 / (1440/360) = 110 pages or 22 fully printed pages
• One 8.5 x 11 page is 93.5 inch/sq.
• Total ink cartridge yield is page square inches x page yield @ 100% = 93.5 inch/sq. x 22 pages  = 2057 square inches*
• Cost of one square inch of ink is Cartridge cost / cartridge yield = $ 12.34 / 2057 = $ 0.006

Cost of one square inch of printed image on average Luster paper = 0.0084 + .006 = 0.0144

Average print cost and cartridge yields per print size,*

Cost below, does not include cost of image processing and equipment depreciation.

The Cost of the Ink you buy

Have you ever wondered about the cost of the ink when you purchase a cartridge for your printer? Everyone has. When you have to pay $28.95 for an ink cartridge replacement you can not help but wonder why so much!

Actually, the ink at cartridge retail is far more then most of us can comprehend. Far more then the cost of most exotic liquids we know of. Most cartridges hover around 1.5 ML to 2.25 ML. For this example lets use a 2 ML cartridge at a cost of $28.95. Lets calculate the hypothetical cost per gallon.

One Liter contains 1000 ML thus, we get 500 - 2 ML cartridges from a Liter. Therefore, a Liter would retail at 500 x $28.95 = $14,475.00.

There are 3.785 Liters in a Gallon so, $14,475.00 x 3.785 = $54,787.87

That is a lot of money. This astonishing figure is probable not realistic because there is, after all, the packaging however, it demonstrates that the ink business is a worthwhile business deserving all the warning labels we find on our printer not to substitute the ink. The question why the high prices? To the best of my knowledge there is no answer for this and no articles have been written or outcries from user groups have been heard other then it appears to support the inkjet printer marketing effort. The makeup of today's photo printers are highly sophisticated and must have cost a lot of recourses to develop. The manufacturers reasoning seems to be, if you want a cheap printer, then pay for the ink.