Us next to everything else, line by line. Every cell below comes from each product’s own public pages, read on September 8, 2026, with links at the bottom. If we got something wrong, tell us and it gets fixed the same day. One thing to know before you read: CiteStamp uses no AI to decide anything. A reference resolves in the public registries or it doesn’t, and you can watch it happen in your own network tab.
Four other tools draw a map of the literature. This table is about what the map is made of and who can use it.
| Tool | Free tier | Walk the graph | Typed claims | Signed kept apart from machine | Preprints & deposits | For AI agents | Open data | Full price |
|---|---|---|---|---|---|---|---|---|
| CiteStamp | Unlimited, no account | Yes: a live map of a paper’s recorded citations, click any node to open its own | Yes: supports, refutes, extends, uses method, uses data, signed by a named researcher | Yes: two tiers, labelled in every answer, never blended | Yes: SSRN, Zenodo deposits and datasets get a page and a map | Yes: MCP endpoint, no key, no account | CC0, fork it | $35/yr for automation; the graph and the checks are free |
| scite | Free Connect plan, no card, with 25 MCP credits a month; paid plans start with a 7-day trial | Not advertised | Smart Citations sort citations into supporting, contrasting and mentioning. Nobody signs one | Not advertised | Yes: “patents, clinical trials, grants, preprints, and datasets” | MCP, metered by credits; API on the Pro plan | Closed, licensed | $20/mo Basic, $50/mo Pro; annual billing saves $96 and $120 |
| Connected Papers | 5 graphs a month | Yes, a similarity graph. Their words: “Connected Papers is not a citation tree” | No | No: every connection is a machine similarity score | Not stated; built on the Semantic Scholar corpus | Not advertised | Closed, built on an open corpus | $6/mo academic billed $72 a year; $20/mo business billed $240 a year |
| ResearchRabbit | Unlimited searches, up to 50 seed articles | Yes: “turn one paper into a map of ideas” | Not advertised | Not advertised | Not stated | Not advertised | Closed | $10/mo on the annual plan, $12.50 monthly |
| Litmaps | 2 maps, 100 articles each | Yes: “see your research from a bird’s-eye view” | Not advertised | Not advertised | Not stated | Not advertised | Closed | $10/mo, or $120 a year |
The free front door. Several tools check a reference list; here is what each one does with your text while it checks.
| Tool | Free tier | Your text… | Checks a pasted list | Retractions | Full price |
|---|---|---|---|---|---|
| CiteStamp | Unlimited, no account | stays in your browser | Yes: does each reference resolve, does the DOI match the title it claims, and no AI in the loop | Yes, free watchlist, daily | Free; $35/yr adds continuous checking while you write |
| scite Reference Check | Listed as a product; the pages we read do not describe a free tier for it | Not described on the pages we read | Not described on the pages we read | Not described on the pages we read | inside the $20 and $50/mo plans |
| Paste-in AI checkers | Metered or paid (CiteMe: 3 checks a month free; Citely: $9 one-off trial, no free tier) | sent to their servers | Yes, by an AI; Citely: “advanced AI algorithms analyze your text” | Not stated | $0–19/mo |
| Zotero + Retraction Watch | Free | anonymized lookups | No | Yes, for your library and documents cited through its word-processor plugin | Free |
| Recite | 2 uploads a day, first 2,500 words and 50 references | whole document uploaded | No: it checks that in-text citations and the reference list agree; paid tiers add “enhanced DOI feedback” | Paid tiers: “retracted references highlighted” | $9/mo, $90/yr, $11 for one month, $7 for three days |
“Not advertised” means the product’s public pages do not claim the capability; it may exist unstated. “Not stated” means the pages we read do not say either way. “Paste-in AI checkers” groups CiteMe, Citely and similar single-purpose sites; swanref.org, listed here in July, did not resolve on September 8, 2026.
A word about the other maps. Connected Papers, ResearchRabbit and Litmaps are good at what they are for, which is finding papers you have not read yet. Connected Papers says so plainly: its graph is similarity, not citation. None of the three records who said what about a paper, none lets an author sign a typed claim, and none answers an AI assistant without an account. That is the difference in kind, and it is why the map here is free without a cap.
A word about Zotero: its retraction alerts are genuinely well built. Anonymized lookups, designed so the contents of your library are never shared. If your papers live in Zotero, turn them on; nothing here competes with that. What it does not do is check the bibliography you are writing right now, the pasted, AI-drafted one that has never been near your library. That is our job, and both tools are free, so use both.
And a word about method: most checkers in the second table answer with an AI’s opinion. CiteStamp answers with a record lookup in Crossref, DataCite and OpenAlex that either finds the paper or does not. That is why the checks can be free, why nothing needs uploading, and why you can audit every claim we make with your browser’s network tab open.
Sources, read September 8, 2026: scite pricing and scite.ai · Connected Papers pricing and about · ResearchRabbit pricing and home · Litmaps pricing and home · CiteMe pricing · Citely · Zotero retraction notifications · Recite pricing. Prices are the vendors’ listed figures; annual equivalents shown where they advertise annual billing.