Alternatives and competitors

Sites like ClinicalTrials.gov

The 20 closest clinical trials registry alternatives to ClinicalTrials.gov, ranked by what they actually offer, and the 4 technologies behind it.

Looking for an alternative to ClinicalTrials.gov? The closest matches are nih.gov, MedlinePlus and Europe PubMed Central. We match sites by what they actually offer, from their homepages, Wikidata and a summary by Claude, in any language. Vote on each alternative and leave a short note to help the next person choose.

Neighbours
k = 20
Sites searched
4,032
Vector
384-d
Query
11 ms

01 · Entity

About ClinicalTrials.gov

ClinicalTrials.gov clinicaltrials.gov

ClinicalTrials.gov

Wikidata: United States government registry of clinical trials

Top 10K · #3,641 English 4 technologies Crawled Nov 6, 2026
Visit ClinicalTrials.gov

Summary by Claude

A public database of privately and publicly funded clinical studies worldwide, run by the U.S. National Library of Medicine, where users can search trial registrations, eligibility criteria, locations and posted results, and sponsors can register studies.

Who it’s for
Patients, clinicians, researchers, trial sponsors
Business model
Government funded

02 · Embedding space

Competitor map

Each alternative by how close its vector is to ClinicalTrials.gov’s (x) and how much traffic it gets, how much of the stack it shares, or where it sits in the embedding space itself (y). Lines split each axis at the median. Hover for the numbers, click to jump to it in the list.

similarity × popularity

CNRSUnited States CongressNational AcademiesPsychology TodayCDCmedRxivNational Cancer InstituteEurope PubMed CentralMedlinePlusnih.gov

03 · Nearest neighbours

Alternatives to ClinicalTrials.gov

Thumbs up if it’s a real alternative to ClinicalTrials.gov, thumbs down if it isn’t.

Only in English

We can’t read clinicaltrials.gov’s homepage (too little text on the homepage), so it’s compared on what Wikidata and Wikipedia say about it.

  1. 01
    nih.gov Top 1K English

    US government medical research agency

  2. 02
    MedlinePlus medlineplus.gov Top 10K English

    MedlinePlus - Health Information from the National Library of Medicine

    Find information on health conditions, wellness issues, and more in easy-to-read language on MedlinePlus, the up-to-date, trusted health information site from the NIH and the National Library of Medicine.

  3. 03
    Europe PubMed Central europepmc.org Top 10K English

    database of biomedical research

  4. 04
    National Cancer Institute cancer.gov Top 10K English

    Comprehensive Cancer Information - NCI

    Accurate, up-to-date, comprehensive cancer information from the U.S. government's principal agency for cancer research.

  5. 05
    medRxiv medrxiv.org Top 10K English

    medRxiv.org - the preprint server for Health Sciences

    medRxiv - the preprint server for biology, operated by openRxiv, a nonprofit organization dedicated to advancing scientific communication

  6. 06
    CDC cdc.gov Top 1K English

    Centers for Disease Control and Prevention | CDC

    United States government public health agency

  7. 07
    Psychology Today psychologytoday.com Top 10K English

    Psychology Today: Health, Help, Happiness + Find a Therapist

    View the latest from the world of psychology: from behavioral research to practical guidance on relationships, mental health and addiction. Find help from our directory of therapists, psychologists and counselors.

  8. 08
    National Academies nationalacademies.org Top 10K English

    National Academies of Sciences, Engineering, and Medicine

    Our work helps shape sound policies, inform public opinion, and advance the pursuit of science, engineering, and medicine.

  9. 09
    EBSCO Information Services ebsco.com Top 10K English

    EBSCO - Research Databases, EBooks, Discovery Service

    EBSCO is the leading provider of research databases, e-journals, magazine subscriptions, ebooks and discovery service for academic libraries, public libraries, corporations, schools, government and medical institutions

  10. 10
    Our World in Data ourworldindata.org Top 10K English

    Our World in Data

    Research and data to make progress against the world’s largest problems.

  11. 11
    United States Congress congress.gov Top 10K English

    bicameral legislature of the United States

  12. 12
    Pew Research Center pewresearch.org Top 10K English

    Pew Research Center | Nonpartisan, nonadvocacy, public opinion polling and data-driven social science research

    Numbers, Facts and Trends Shaping Your World

  13. 13

    National Archives | Home

    National Archives and Records Administration

  14. 14
    CNRS cnrs.fr Top 10K English

    Centre national de la recherche scientifique (CNRS)

    Le Centre national de la recherche scientifique est le plus grand organisme public français de recherche scientifique. Il exerce son activité dans

  15. 15
    NSF nsf.gov Top 10K English

    NSF - U.S. National Science Foundation

    NSF is an independent federal agency that supports science and engineering in all 50 states and U.S. territories.

  16. 16
    www.nhs.uk Top 10K English

    NHS website for England - NHS

    Find information and services to help you manage your health.

  17. 17
    Healthline healthline.com Top 10K English

    Healthline: Medical information and health advice you can trust.

    We're committed to being your source for expert health guidance. Come to us in your pursuit of wellness.

  18. 18
    JSTOR jstor.org Top 10K English

    Client Challenge

    distributor of eBooks and other digital media

  19. 19
    United States Copyright Office copyright.gov Top 10K English

    U.S. Copyright Office | U.S. Copyright Office

    Copyright Office Homepage

  20. 20
    Library of Congress loc.gov Top 1K English

    Home | Library of Congress

    The world's largest library. View historic photos, maps, books and more. Contact experts for help with research. Plan a visit. Home of U.S. Copyright Office.

Ranked by score: the cosine similarity of each site’s vector to clinicaltrials.gov’s, less a small penalty for generic sites that are close to everything. Highlighted technologies are ones ClinicalTrials.gov uses too. Votes and comments come from visitors and don’t change the ranking.

04 · Fingerprints

Technology

What ClinicalTrials.gov is built with, and what its closest competitors use, from its homepage’s code and its DNS records.

SimilarSiteSearch

Competitors by meaning, stacks from the source. Data from public homepages and DNS.

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