How Much Ink Do Epson Printers Waste?

Do you ever wonder how much ink your printer wastes? We do, so we did some testing.

First, we use the Epson 9900 printer, and we always use 700ml cartridges. When the printer thinks the cartridge is at about 2%, it starts blinking like this (notice our yellow and light light black are both blinking):

We've long suspected that when the cartridge is at 1%, that it isn't really. The light will blink for days, and sometimes weeks. But it isn't the blinking that's annoying. We don't care about that. What's annoying is that when the cartridge is at 1%, you can no longer perform cleanings, and everyone knows that you need to clean very often. Sometimes we'll have to clean multiple times in a day.

At a certain point we need to give up and change the cartridge because we just can't take the time to switch out cartridges multiple times a day. Besides, if you swap out your cartridges multiple times a day like that you're really risking introducing air into the lines, which will also cause misprints.

So here's what we did to test our theory that ink is still left, and that the Epson 9900 is way off when it says 1% ink remaining. In fact, we've proved here that the Epson 9900 really has no clue how much ink is left. It's guessing at best, but it's so far off it's laughable.

First we took some full cartridges and weighed them to see how much they weigh full. We made sure we weighed several to account for any errors in the scale. We came out with about 1012 grams per cartridge:

Then we weighed the full ink with the bag (Just so we'll know for future reference):

Then we weighed the bag (about 17 grams):

Then we weighed on a triple beam to make sure our electronic scale is accurate (it turns out it rounds down to the nearest gram). We cross check the weight here on several occasions between two scales, because we don't want anyone accusing us of not being accurate:

Next we cut open a cartridge of light light black ink. Our printer said we only had 1% ink left. First we weighed the cartridge before we cut it open, and it weighed 374g. Then we cut open the cartridge and weighed the ink inside. We get 119 grams. :

We then weighed the empty cartridge (it weighs about 255 grams):

From this calculation we can determine that one ml of ink weighs about 1.08 grams. We get this by taking the weight of the full cartridge (1012 grams) minus the weight of the empty cartridge (255 grams). We've weighed a few like this, and we've come to the conclusion that the ink does weigh about 1.08 grams per milliliter, and a full cartridge has about 757 grams of ink.

This means that this cartridge, which the Epson 9900 says has 1% left of ink actually has about 15% ink remaining.

We checked another based on our calculation. We took a cartridge of light cyan that had been at 1% for a while, and the printer could no longer run cleanings with it. We weighed it, cut it open, weighed the cartridge and the ink, and verified our calculation. (Actually we've done this about a dozen times now and each time our result is within a gram based on this calculation)

We have two other cartridges in our Epson 9900 now that are blinking 1% and we had to remove them both for cleaning, but our math tells us that they have 16% and 18% remaining respectively.

So according to our calculations, we only get about 600ml of ink usable out of a 700ml cartridge. This means, on average, that we throw about $35 worth of ink in the garbage when the printer starts rejecting a cartridge because it's low on ink. It also means the Epson 9900 has about a 1500% margin of error on low ink.

To test how much ink is in a full cartridge, we took a 700 ml cartridge that was bad (Epson did kindly give us a free replacement) and we emptied it and measured and weighed the ink. We did this because one of our distributors said that they think (they don't know) Epson puts in more than 700ml to account for some of the waste. So I emptied a full cartridge into a 750 ml scotch bottle (12 yr old Glenmorangie Port Barrel aged). The 700 ml cartridge did not fill the bottle. We measured and weighed, and the answer is that Epson does not put extra ink in the cartridges to compensate for ink waste. There was almost exactly 700ml in the cartridge. No extra. No more. No less.

The final answer is that between 15%-18% of our ink is wasted, not counting cleanings.  

3.16.2012 - Today we weighed the 220ml cartridge for the Epson 4880. Completely empty those weigh 151g, so you can do the same math for those. One ml of ink weighs 1.08 g. 


Although our experience is that when the 4880 stops cleaning due to low ink, that it's actually got about 30-40 ml left in a 220ml cartridge. 

700 ml empty cartridge for the Epson 9900 = 255g
350 ml empty cartridge for the Epson 9900 = 195g
220 ml empty cartridge for the Epson 9900 = 151g

NB: Sept 2012: We have over the last year continued to weigh every single ink cartridge when it's done. We empty them, weight the ink, weigh the cartridge etc. We also weigh each cartridge when we first open it, and our experience is that the 700 ml cartridges weigh between 1003 and 1113 grams when they are brand new. Essentially after a year of doing this now we're 100% sure that our calculations are at least 99% correct. The bottom line is that we are throwing away 700 ml cartridges with 100 ml of ink still left in them, because you really can't keep printing with a bunch of cartridges that are showing 1% - it's completely impractical and impossible to work when you have to stop and swap cartridges every other print during routine cleaning or auto cleaning.