medRxiv API

medRxiv is a preprint server for health sciences. The API is identical to bioRxiv's API -- same endpoints, same response format -- just use medrxiv as the server parameter.

Important: Like bioRxiv, there is no keyword search. Use Europe PMC (SRC:"PPR" AND PUBLISHER:"medRxiv"), Semantic Scholar, or OpenAlex for keyword searches of medRxiv content. PubMed coverage of preprints is selective.

Base URL

https://api.biorxiv.org

(Same base URL as bioRxiv -- the server is specified in the path.)

**Use api.biorxiv.org, not api.medrxiv.org.** The api.medrxiv.org host answers some paths but is not equivalent, and its failures are not graceful (verified 2026-07-27):

Every example below uses api.biorxiv.org.

Authentication

None required. Fully public API.

Key Endpoints

1. Content Detail -- Browse by date range

GET /details/medrxiv/{interval}/{cursor}/{format}

Optional: ?category=cardiovascular%20medicine (use URL-encoding for spaces)

Examples:

https://api.biorxiv.org/details/medrxiv/2024-01-01/2024-01-31/0
https://api.biorxiv.org/details/medrxiv/5
https://api.biorxiv.org/details/medrxiv/10d

2. Content Detail -- DOI lookup

GET /details/medrxiv/{doi}/na/{format}

Example:

https://api.biorxiv.org/details/medrxiv/10.1101/2021.04.29.21256344/na/json

3. Published Article Links

GET /pubs/medrxiv/{interval}/{cursor}
GET /pubs/medrxiv/{doi}/na

Links preprints to their published journal versions. Accepts both preprint DOI and published DOI.

Response Format

Same as bioRxiv:

{
  "messages": [{
    "status": "ok",
    "category": "all",
    "interval": "2024-01-01:2024-01-03",
    "funder": "all",
    "cursor": 0,
    "count": 30,
    "count_new_papers": "46",
    "total": "60"
  }],
  "collection": [{
    "title": "Paper title...",
    "authors": "Surname, A.; Surname, B.",
    "author_corresponding": "Full Name",
    "author_corresponding_institution": "Institution",
    "doi": "10.1101/2021.04.29.21256344",
    "date": "2021-05-03",
    "version": "1",
    "type": "PUBLISHAHEADOFPRINT",
    "license": "cc_by_nc_nd",
    "category": "cardiovascular medicine",
    "abstract": "Full abstract text...",
    "published": "10.1371/journal.pone.0256482",
    "server": "medRxiv"
  }]
}

Pagination

**30 results per page on /details/, 100 on /pubs/** -- same as bioRxiv, and the same silent hazard: cursor is an absolute record offset, out-of-step values return HTTP 200, and stepping a /details/ walk by 100 skips records 30-99 of every hundred while looking successful. Step by the count the response reported. See the Pagination and messages sections of references/biorxiv.md for the full behavior, including why total and count_new_papers differ and which endpoints expose no counts at all.

scripts/paginate.py --api medrxiv implements the walk with the correct step.

Rate Limits

No documented rate limits. No authentication required.

Categories

These are website slugs; use spaces (URL-encoded) or underscores in API category values, e.g. cardiovascular_medicine.

addiction-medicine, allergy-and-immunology, anesthesia, cardiovascular-medicine, dentistry-and-oral-medicine, dermatology, emergency-medicine, endocrinology, epidemiology, forensic-medicine, gastroenterology, genetic-and-genomic-medicine, geriatric-medicine, health-economics, health-informatics, health-policy, health-systems-and-quality-improvement, hematology, hiv-aids, infectious-diseases, intensive-care-and-critical-care-medicine, medical-education, medical-ethics, nephrology, neurology, nursing, nutrition, obstetrics-and-gynecology, occupational-and-environmental-health, oncology, ophthalmology, orthopedics, otolaryngology, pain-medicine, palliative-medicine, pathology, pediatrics, pharmacology-and-therapeutics, primary-care-research, psychiatry-and-clinical-psychology, public-and-global-health, radiology-and-imaging, rehabilitation-medicine-and-physical-therapy, respiratory-medicine, rheumatology, sexual-and-reproductive-health, sports-medicine, surgery, toxicology, transplantation, urology

Official sources reviewed 2026-09-30

• https://api.biorxiv.org/