Get a free DOI in about 10 minutes
PeerSigned reviews work that has a DOI. That's not a paywall. A DOI is free, it takes minutes, and it's yours forever regardless of what happens here. It's the identifier reviews attach to, which is what makes the record permanent and portable.
Any route below works. We don't care which one you pick, we get nothing from any of them, and none of them is a recommendation. The annotations are just the facts you'd want before choosing.
Zenodo free · instant · unscreened · DataCite DOI
Operated by CERN. Make an account, upload your PDF, fill in the metadata form, publish. You get a DOI immediately, no moderation queue, no approval step. The fastest route by a wide margin. Nobody screens the content, so a Zenodo DOI carries no vetting signal by itself. That's fine: the review is the signal, the DOI is just the anchor.
Preprints.org free · screened · typically a few days
Runs a moderation pass for scope and basic standards before posting, which usually takes some days. Operated by MDPI. Slower than Zenodo, with a light screen attached.
arXiv free · endorsement required · DataCite DOI
The standard venue in physics, math, and CS, and the hardest of these to enter as an independent. Since January 2026 an institutional email no longer gets you auto-endorsed, and the CS categories stopped accepting position and review papers. If you already hold endorsement in your category, use it. If you don't, expect friction, and know that Zenodo works just as well as an anchor for review.
ICSAC free · screened · narrow scope
The International Center for the Study of Advanced Complexity accepts submissions in complexity and consciousness studies, with ORCID gating and editorial screening. Narrower scope and a harder gate than the routes above.
One detail that matters
Submit a version DOI, not a concept DOI. Reviews attach to a specific, frozen version of your paper, so the record can't drift out from under them. Zenodo gives you both kinds; the version DOI is the one tied to the exact file you uploaded.
Back to the front page when you have your DOI.