Confirming the right cartridge for the printer you already have

After reading this you will know which numbers to take off your printer, which lookup to open for your brand, and what each one actually returns. For Epson and Brother, the finder takes a model number. For HP, the tool most often linked does something different — it returns a compatibility verdict, not a part number — and this page says so plainly rather than promising otherwise.

The short version: do not order from a listing title. Find your printer's model number, its serial number, and the number printed on the cartridge now in the machine. Open the manufacturer's own lookup for your brand. Write down what it tells you and the URL that told you. Everything below is why that order of operations matters, what each brand's tool actually answers, and what to do when a tool asks for something you cannot find or answers a different question than the one you asked.

Why the family number alone does not settle which generation you need

HP's Printer Cartridge Lookup has three required fields: Printer Model, Printer serial number and Printer cartridge number. Two of those three are dropdowns. Printer Model is a dropdown, and so is Printer cartridge number — and the numbers it offers you depend on the model you picked. The tool carries that mapping in its own page source. Pick HP Officejet 5200 series and the cartridge list offers 63, 123, 302 and 803. Pick HP Deskjet 2600 series and it offers 65, 123, 304 and 803. Pick HP Deskjet Ink Advantage 2600 series and it offers 652, 664 and 680.

Two things follow from that, and they are not what you would guess. First, the model does not narrow you to a single family number: every one of the six printer series in that tool maps to three or four different family numbers. A model and a family number are not a matched pair. Second, the serial number is not the field that produces a family number at all. It is the field that settles which generation of that family your individual machine takes.

The tool's answers show this. One possible result reads: "This Printer uses newer generation HP cartridges. All HP cartridges with a warranty end date after Aug 15, 2019 are compatible with this Printer." The other reads: "This printer uses both older and newer generation print cartridges. You may continue to use your older generation cartridges, or any newly purchased HP cartridges for this printer." The tool then tells you to check the date on the back of the cartridge box to verify the warranty end date. Neither answer is a part number.

So the model narrows the candidates and the serial number settles the generation. That two-step reading is an inference — HP publishes no sentence explaining its tool this way — but it follows from two things that are in the page as served: the model-to-cartridge mapping behind the dropdown, and the two result strings. The narrow conclusion is the safe one: two machines can share a model name and a cartridge family number and still differ in which generation of that family they accept.

One limit matters more than any of the above. The model list in that tool covers six printer series: Deskjet 2600, Deskjet Ink Advantage 2600, Deskjet Ink Advantage 5000, Deskjet Ink Advantage 5200, Envy 5000 and Officejet 5200. If your HP is not one of those, this tool has nothing to say about your machine, and no other HP model-to-part-number lookup could be read from here. See the table and the limits section below.

The three numbers to write down, and where they are

HP's lookup gives the locations for its own machines, and the same physical places are worth checking on any brand:

1. Serial number — HP states these are "found on the barcode stickers located at the back of your printer, or sometimes inside the ink cartridge access area." Open the lid where the cartridges sit and look on the inside wall before you conclude there is no label. The field is usually printed as Serial Number, Serial No, S/N or SN.
2. Cartridge number — HP states these are "printed on the top or front of the ink cartridge." Pull the old cartridge out and read the number off the cartridge itself, not off the box you kept.
3. Model number — printed on the front or top panel, and on the original box. Brother's supplies search asks for the machine model number with the hyphen removed, so note the exact string including any suffix letters.

Write all three down before you open any website. Every lookup below wants at least one of them, and HP's wants all three.

Where to look it up, per brand

Use the manufacturer's own tool rather than a search engine or a marketplace listing title. The table below lists every path checked for this page on 22 September 2026, including the ones that failed. The failures are the point: several paths that look exactly right are not.

The Brother row is the useful caution. brother-usa.com/supplies is a real page on the manufacturer's real domain and it is the wrong department entirely. A URL that looks right is not a URL that is right. The HP rows make a second point: of the four HP paths checked, one answers a different question than the one you asked, two are places to buy rather than lookups — a shop category and a product marketing page — and one could not be read. An Epson or Brother owner is well served here. An HP owner whose printer is outside those six series, and a Canon owner, are not — and saying so is more useful than sending them somewhere that will not help.

Standard versus XL is a capacity question, not a fit question

Shoppers do raise the standard-versus-XL choice at the point of sale rather than at the manufacturer. A Best Buy product Q&A for the HP 62XL tri-color cartridge has a buyer asking "what is the difference between the 62xl vs 62 ink cartridges when buying for the 7645 HP what should I get 62 or 62xl". That is cited only as evidence the question gets asked at retail; the answers under it are user-supplied and are not used as fact here. Whether it is a fit question or a cost question is worth separating, because the manufacturer pages below suggest it is a cost question.

Epson's own product pages make the distinction visible. Epson lists both the standard 802 black (T802120-S) and the high-capacity 802XL black (T802XL120-S) as ink for the WorkForce Pro WF-4740. The compatible-printer list on the 802XL page covers WorkForce Pro WF-4720, WF-4730, WF-4734, WF-4740, EC-4020, EC-4030 and EC-4040, plus the Business Edition variants of three of those. The list on the standard 802 page is the same set of machines.

Inferred from those two lists: within that family, the standard and XL parts fit the same printers, and the difference between them is stated capacity — Epson names one Standard Capacity and the other high-capacity. Note what the inference does not cover. Neither Epson product page publishes a page-yield figure; both were checked. So for yield you need the figure printed on the cartridge box, or in your printer's own specifications, usually labeled Page Yield or Cartridge Yield.

Once you have that figure, the decision is arithmetic rather than compatibility. Divide what the standard cartridge costs you by its stated yield, divide what the XL costs you by its stated yield, and compare the two numbers. Use whatever you would actually pay, from wherever you actually buy. The larger cartridge is not automatically the cheaper one per page, which is why it is worth doing rather than assuming. Treat the result as a comparison and not a forecast: HP states that ISO standard page yields "should be used only as a starting point for comparison purposes and not to predict the actual yield you will get from your HP printer and cartridge." The fuller version of this arithmetic, including running costs beyond ink, is on the cost-per-page guide.

One caveat on the pattern itself. That observation covers one cartridge family on one manufacturer's pages. Some models list only certain variants. Confirm on the manufacturer's page for your own model rather than assuming it holds everywhere.

The cartridge currently in the machine may not be the one to reorder

HP states, on its own page explaining how it measures inkjet page yields, that "some HP inkjet printers include an 'introductory cartridge' in the printer box, which may print less than an HP replacement cartridge" and that "HP's printer packaging indicates whether introductory cartridges are included with the printer". The same page states that "Some HP inkjet printers use ink from the first cartridges installed for printer start up" and that "This one-time ink usage is not included in the ISO 24711 test and could impact the yield for your very first cartridge."

That last point is worth understanding before you compare any two yield numbers. HP describes the ISO 24711 method as follows: "Under the ISO 24711 testing guidelines, a standard set of five 8 1/2 x 11 pages is printed continuously until the cartridge reaches end-of-life." Printed continuously, on a standard set of pages, from a full cartridge. Your first cartridge in a new machine is doing something else as well — filling the system — and HP says that start-up usage sits outside the test.

The practical consequence is twofold. The part number printed on the cartridge you are pulling out of a new machine is not automatically the part number to reorder, so check the lookup rather than the used cartridge. And a first cartridge that seems to run out quickly is not necessarily a fault; it is the main reason a printer's advertised yield and your first refill interval disagree.

Chips and firmware: what HP actually says

HP's supplies security page states: "HP uses Dynamic Security to authenticate Original HP Cartridges and help prevent the potential introduction of security vulnerabilities through counterfeit or cartridges with non-HP chips that may come with potential risks." HP scopes that page precisely: it applies to HP Office-class printing systems, which it defines as select Enterprise and Managed devices with FutureSmart firmware 4.5 and above, Pro devices, and LaserJet models 200 and up, "with respective Original HP Toner, PageWide, and Ink Cartridges. It does not include HP integrated printhead ink cartridges." Those three supply types are named separately, and the exclusion is worth reading closely if your cartridge has the printhead built into it.

That is reported here as a manufacturer statement and nothing more. No claim is made on this site about whether any particular third-party, compatible or remanufactured cartridge will work in any particular machine, and no claim is made about the quality or safety of such cartridges. If that matters to your purchase, the question to ask the seller is a specific one: which printer firmware versions has this part been confirmed against, and what is the return policy if it is rejected.

What not to rely on

• A marketplace "compatible with" table. It is written by a seller, it is frequently copied between listings, and it is not checked against your machine. Sharing a category name never establishes fit.
• A yield figure in a retailer listing rather than the manufacturer's own wording. HP states plainly that ISO standard page yields "should be used only as a starting point for comparison purposes and not to predict the actual yield you will get from your HP printer and cartridge." A retailer repeating a number without that qualification has dropped the part that mattered.
• The old empty cartridge on its own. It may have been the wrong part all along, it may be a lower-yield introductory cartridge, or it may have been bought in a different sales region.
• A guessed lookup URL. Nine paths were checked for this page. Two turned out to be working model-based finders. One works but answers a different question. Three were not lookups at all — a shop category, a marketing page, and sewing supplies. Three could not be read from here at all.

Before you order: six things to have written down

1. Printer model, exactly as printed on the machine including suffix letters.
2. Printer serial number, from the rear label or inside the cartridge access door.
3. Part number printed on the cartridge currently in the machine.
4. The country or region where the printer was bought, if it was not where you are now.
5. Standard or high-yield, decided on cost per page using the yield figure from the box or the printer's specifications.
6. The manufacturer page URL that confirmed the match, and the date you checked it.

What could not be verified here

Regional part numbering and region locking are widely discussed, but no primary manufacturer support document establishing the mechanism could be opened from here. HP's community threads on regionalisation return HTTP 403 to automated requests, and secondhand summaries are not a source. So this page makes no claim about how regional cartridge coding works, and offers no explanation for why HP's own tool lists three or four different family numbers for a single printer series. If your printer was bought in one country and you are buying cartridges in another, treat that as a question for the manufacturer's support line before you order.

Canon's Ink & Toner Finder at usa.canon.com/shop/ink-finder returned HTTP 403 to an automated request. The server answered and refused, so nothing about what it asks for or returns can be described here. It is named rather than omitted so a Canon owner has a starting point, but it is not linked as a checked destination, and "we could not read it" is not the same as "it does not work".

The same applies to support.hp.com/us-en/supplies, which returns HTTP 200 but serves an application shell whose content loads in the browser. It may well be a working supplies finder for a human reader. It could not be read from here, so nothing is claimed about it. No HP tool that returns a part number from a model number alone was verifiable for this page.

The one action to take now

Epson or Brother: open your brand's finder from the table, enter the model number, and read the part numbers it lists. Buy that string, wherever you buy it. HP: if your printer is one of the six series its Cartridge Lookup covers, enter the model, pick your cartridge number from the list it offers, and add the serial number — what you get back is whether your machine takes newer-generation cartridges or both, which is the thing a listing title cannot tell you. If your HP is outside those six series, take the number off the old cartridge and confirm it against HP's own product page for that cartridge before ordering. Then, before choosing between the standard and the XL version, do the division in the section above. If the underlying problem is that the printer sits idle for weeks and fights you when you need it, the cartridge is not the variable to change — the light-use guide covers that case.

Check it on your own equipment

These take you to the manufacturers and standards bodies the page draws on, so you can look up your exact model.

• Official support page
  HP Printer Cartridge Lookup (opens in a new tab)Three required fields: Printer Model and Printer cartridge number are dropdowns, Printer serial number is a text box. The cartridge list offers only the numbers HP maps to the model you picked. The answer is a generation verdict — whether your machine takes newer-generation cartridges or both — not a part number. The model list covers six printer series. — support.hp.com
• Official support page
  Epson Ink Finder (opens in a new tab)A single search box reading "Enter a Printer Model or Ink Code", with the example "WorkForce Pro WF-4740, 802, T802120". It works from either direction: type the printer model, or type a code off the old cartridge. — epson.com
• Merchant listing
  Brother Shop Ink & Toner (supplies finder) (opens in a new tab)The heading "Shop Ink & Toner" and the instruction "Enter your Machine Model Number or your Supply Number below, excluding the hyphen." The path redirects to brother-usa.com/c/shop/ink-toner. Note that brother-usa.com/supplies without the /ink-and-toner path takes you to sewing and embroidery supplies instead. — www.brother-usa.com
• Manufacturer specification
  HP: how inkjet page yields are measured (ISO 24711) (opens in a new tab)HP's own description of the ISO 24711 test — five standard pages printed continuously to end-of-life — plus its statements on start-up ink, introductory cartridges, and why ISO yields are a comparison starting point rather than a prediction. Read it before comparing a standard and an XL cartridge on yield. — www.hp.com