Us next to everything else, line by line. Every cell below comes from each product’s own public pages as of July 13, 2026 — links at the bottom, and 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 — no “95% confidence”, and you can watch it happen in your own network tab.
| Tool | Free tier | Your text… | AI-invented refs | Wrong DOI | Retractions | Open data | Full price |
|---|---|---|---|---|---|---|---|
| CiteStamp | Unlimited, no account | stays in your browser | Yes | Yes | Yes — free watchlist, daily | CC0 — fork it | $35/yr for automation; the checks are free |
| scite | None — 7-day trial, card required | uploaded for Reference Check | Not advertised | Not advertised | Yes — paid tier | Closed, licensed | from $20/mo ($240/yr) |
| Connected Papers | 5 graphs/month | server-side | No | No | No | Closed (built on open corpora) | $72/yr academic |
| ResearchRabbit | 50 seed articles | server-side | No | No | Alerts in the $10/mo tier | Closed | ~$120/yr |
| Litmaps | 1 map, 100 articles | server-side | No | No | No | Closed | $120/yr |
| Paste-in AI checkers | Metered or login-walled (25 refs/mo; Google sign-in; or none) | sent to their servers | Yes | Varies | None we found | Closed | $0–19/mo |
| Zotero + Retraction Watch | Free | anonymized lookups | No | No | Yes — your saved library only | Open source | Free |
| Recite | 2 uploads/day | whole document uploaded | No — consistency & style only | No | No | Closed | paid plans |
“Not advertised” means the product’s public pages do not claim the capability — it may exist unstated. “Paste-in AI checkers” groups CiteTrue, CiteMe, Citely, SwanRef, and similar single-purpose sites.
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 the difference in kind: most tools in this table answer with an AI’s opinion. CiteStamp answers with a record lookup — Crossref, DataCite, 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, as of July 13, 2026: scite pricing · Connected Papers pricing · ResearchRabbit pricing · Litmaps pricing · CiteMe pricing · Citely · SwanRef · Zotero retraction notifications · Recite. Prices are the vendors’ listed figures; annual equivalents shown where they advertise annual billing.