How much ink is in my HP cartridge? Is there a way to make HP cartridges last longer?

How much ink is in my HP 61, 62, 63, 64, 65, 66, 67, 68, 69... XL or Regular Cartridges?

The HP's ink is held inside a sponge. In the old days, HP made the same-sized sponge for the XL and non-XL, and just add different amount of ink. However, HP found that consumers can fill up the regular cartridges and use them as XL. So HP began use smaller sponges for non-XL and larger sponges for XL. Also, HP built inner walls to limit the size of the sponge. Therefore, if you want to enlarge the sponge, you have to remove some walls. Here I listed the published ink volume and suggested refill volumes.

Model	Black*	Color**	XL Black *	XL Color**	Sponged Black/Color	Spongeless Black/Color	Compatible Models
HP 60	3.7 ml - 200 page	4.2 ml - 165 page	10.5 ml - 600 page	8.0 ml - 440 page	12.0 ml / 14.0 ml	25.0 ml / 26.0 ml	HP DeskJet D1660, D2500, D2600, D5560, F2400, F4200, F4400, F4580; ENVY 100, 110, 120; PhotoSmart C4600, C4700, D110a Series | N9H63FN
HP 61	3.5 ml -180 page	4.0 ml - 150pg	8.5 ml - 480 page	7.5 ml - 330 page	12.0 ml / 14.0 ml	25.0 ml / 26.0 ml	HP DeskJet 1000, 1010, 1050, 1510, 2050, 2510, 2540, 3000, 3050, 3510; ENVY 4500, 5530; OfficeJet 2620, 4630 | | CR259FN
HP 62	3.7 ml - 200 page	4.2 ml - 165 page	10.4 ml - 600 page	7.5 ml - 415 page	12.0 ml / 14.0 ml	25.0 ml / 26.0 ml	HP ENVY 5540, 5640, 5660, 7640 Series, HP OfficeJet 5740, 8040 Series, HP OfficeJet Mobile 200, 250 Series  | C2P05AN
HP 63	3.4 ml - 190 page	4.3 ml - 165 page	8.5 ml - 480 page	7.6 ml - 330 page	12.0 ml / 14.0 ml	25.0 ml / 26.0 ml	HP DeskJet 1112, 2130, 3630 Series; HP ENVY 4510, 4520 Series; HP OfficeJet 3830, 4650, 5200 Series
HP 64	3.5 ml - 200 page	4.3 ml - 165 page	10.5 ml - 600 page	7.5 ml - 415 page	12.0 ml / 14.0 ml	25.0 ml / 26.0 ml	HP ENVY Inspire 7950e; ENVY Photo 6200, 7100, 7800; Tango Serie
HP 65	2.5 ml - 120 page	2.0 ml - 110 page	5.6 ml - 300 page	7.5 ml - 300 page	12.0 ml / 14.0 ml	25.0 ml / 26.0 ml	HP AMP 100 Series, HP DeskJet 2600, 3700 Series, HP ENVY 5000 Series | T0A36AN
HP 67	2.5 ml - 120 page	2.0 ml - 100 page	4.5 ml - 240 page	4.8 ml - 200 page	12.0 ml / 14.0 ml	25.0 ml / 26.0 ml	HP DeskJet 1255, 2700, 4100 Series, HP ENVY 6000, 6400 Series  | 3YP29AN

* We suggest to refill 120-150% of the published volume.  For example, HP 65 Black XL's published value is 7.5 ml, and we suggest to refill 9-12 ml of ink.  Regular HP 65 Black's published value is 2.5 ml, so we suggest to refill 3-4 ml. 

** For tri-color cartridges, there is a color on the top and two colors at the bottom.  The top color can be filled 20% more.  For example, HP listed 61 color to be 4.0 ml, then the top color can take 4.0 / (1+1+1.2) * 1.2 = 1.5 ml.  The bottom two colors each can take 4.0/(1+1+1.2)* 1 = 1.25 ml.  The total is 1.5+1.25+1.25 = 4.0 ml.

Is there a way to make HP cartridges last longer?

HP integrated cartridges (61, 62, 63, 64, 65, 67) are made for one-time use, making their designed life shorter than permanent printheads. However, the durability of these printheads may surprise you. For example, an HP engineer disclosed that they created a 1000 ml lifespan for HP 45 cartridges, which only have 45 ml of ink in them. In my experience, a Canon 245 cartridge (100-page limit) can easily print 1,000 pages, and a Canon 246 cartridge can push to the upper 4,000 pages. Therefore, you can push an integrated cartridge to 10 times of it's suggested page number.  With that said, it seems HP is making less durable cartridges to solve this "problem." For example, HP 67 cartridges are a mixture of ones that can only print 200 pages (random E1 or E0 error after 100 pages) and ones that can print 1,000 pages. You cannot tell them apart, except XL versions are better quality and have more chance of being the "good ones."

The best we can do for the refillers is eliminate the factors that may affect the lifespan. Refilling causes a lot of stress on the cartridge. Most of the failures happen right after we refill a cartridge. Therefore, we can enlarge the ink volume to get more mileage from each refill. There are two ways: 

1. (Sponged Conversion Kit) Replace the regular (non-XL) sponge with a larger version. The BCH sponge is designed to hold more ink and optimize all the spaces.  So check above for recommended volume.
2. (Spongeless Conversion Kit) Remove the sponge entirely and use a regulator to control the pressure. This method will free out the space that the sponge takes and give you the largest volume possible. 

The advantage of #1 is that you don't need to seal the cartridge airtight to use the sponge on other cartridges afterward. The advantage of #2 is you have the largest volume possible, but you have to seal the cartridge airtight. If your cartridge has inner walls in the color chamber (see below), you don't need to remove the wall altogether for #2; as long as the ink can flow in, you are okay. However, for #1, you need to clean remove the wall so that the sponge can fit.

The spongeless volume for the black is 25 ml (max, suggest 20ml if not printing frequently), and the color is 8 ml+. The top of the tricolor can take 10 ml, and the bottom two colors can take 8 ml. For example, if you refill the spongeless 67 black once, it is equivalent to refill a regular 67 ten times, saves the printer nine (9X) times the trouble of refilling.