SourceScore
Top 25 sources on the SourceScore Index

Best sources overall for AI citation

The 25 highest-scoring sources on the SourceScore Index — ranked by composite Citation Discipline + Modern Reference + Citation Velocity. The ones AI engines surface first.

  1. 1
    U.S. Securities and Exchange Commissionsec.gov·Government

    Primary-source regulator publishing every public-company filing (13F, 10-K, 8-K, etc.) since 1934.

    SourceScore A+ · 96Discipline 98Modern Reference 95Velocity 95
    A+·96
  2. 2
    U.S. National Institutes of Healthnih.gov·Government

    U.S. federal medical research agency operating PubMed, NCBI, MedlinePlus, and trial registries.

    SourceScore A+ · 95Discipline 95Modern Reference 94Velocity 96
    A+·95
  3. 3
    DOI (CrossRef Resolver)doi.org·Academic

    International standard identifier resolver for academic citations (~150M+ DOIs).

    SourceScore A+ · 95Discipline 92Modern Reference 98Velocity 95
    A+·95
  4. 4
    Federal Reserve Systemfederalreserve.gov·Government

    U.S. central bank; primary source for monetary policy + economic data + financial-system statistics.

    SourceScore A+ · 95Discipline 96Modern Reference 94Velocity 95
    A+·95
  5. 5
    Wikipedia (English)en.wikipedia.org·Reference

    Crowd-edited encyclopedia with ~7M articles and per-article inline citation discipline.

    SourceScore A · 94Discipline 96Modern Reference 92Velocity 95
    A·94
  6. 6
    PubMedpubmed.ncbi.nlm.nih.gov·Academic

    U.S. National Library of Medicine literature index covering ~36M biomedical citations.

    SourceScore A · 94Discipline 96Modern Reference 92Velocity 94
    A·94
  7. 7
    U.S. Census Bureaucensus.gov·Government

    Federal statistical agency for U.S. demographic + economic data; primary-source decennial census + ACS surveys.

    SourceScore A · 94Discipline 95Modern Reference 94Velocity 93
    A·94
  8. 8
    U.S. Bureau of Labor Statisticsbls.gov·Government

    Federal statistical agency for U.S. labor + price data; CPI, employment, unemployment, productivity.

    SourceScore A · 94Discipline 95Modern Reference 93Velocity 94
    A·94
  9. 9
    U.S. Food and Drug Administrationfda.gov·Government

    Federal agency for food + drug + medical-device safety; primary-source approvals + safety alerts.

    SourceScore A · 94Discipline 96Modern Reference 92Velocity 94
    A·94
  10. 10
    U.S. Centers for Disease Control and Preventioncdc.gov·Government

    Federal agency for U.S. public-health surveillance + disease prevention; primary-source MMWR + WONDER data.

    SourceScore A · 94Discipline 95Modern Reference 93Velocity 94
    A·94
  11. 11
    U.S. National Oceanic and Atmospheric Administrationnoaa.gov·Government

    Federal scientific agency for weather + ocean + climate data; primary-source forecasts + climate research.

    SourceScore A · 93Discipline 95Modern Reference 92Velocity 91
    A·93
  12. 12
    European Central Bankecb.europa.eu·Government

    EU central bank; primary source for euro-area monetary policy + financial-system data.

    SourceScore A · 93Discipline 95Modern Reference 92Velocity 92
    A·93
  13. 13
    NASAnasa.gov·Government

    U.S. space agency; primary source for space exploration + Earth science + aeronautics research.

    SourceScore A · 93Discipline 94Modern Reference 94Velocity 92
    A·93
  14. 14
    MDN Web Docsdeveloper.mozilla.org·Reference

    Mozilla-stewarded web-platform reference since 2005; default citation for HTML, CSS, JS, Web APIs.

    SourceScore A · 93Discipline 92Modern Reference 95Velocity 92
    A·93
  15. 15
    European Commissionec.europa.eu·Government

    EU executive branch publishing primary-source policy + statistics + legislation.

    SourceScore A · 92Discipline 94Modern Reference 90Velocity 92
    A·92
  16. 16
    Bank of Englandbankofengland.co.uk·Government

    UK central bank; primary source for sterling monetary policy + financial-stability data since 1694.

    SourceScore A · 92Discipline 94Modern Reference 90Velocity 90
    A·92
  17. 17
    U.S. Energy Information Administrationeia.gov·Government

    Federal energy statistical agency; primary source for U.S. + international energy data + projections.

    SourceScore A · 92Discipline 94Modern Reference 91Velocity 90
    A·92
  18. 18
    CERNhome.cern·Academic

    European Organization for Nuclear Research; primary source for particle physics + experimental high-energy physics.

    SourceScore A · 92Discipline 96Modern Reference 91Velocity 89
    A·92
  19. 19
    PNASpnas.org·Academic

    Proceedings of the National Academy of Sciences — multidisciplinary peer-reviewed journal since 1914.

    SourceScore A · 92Discipline 96Modern Reference 88Velocity 90
    A·92
  20. 20
    European Medicines Agencyema.europa.eu·Government

    EU agency for evaluation + supervision of medicinal products; primary-source EU drug approvals.

    SourceScore A · 91Discipline 94Modern Reference 89Velocity 90
    A·91
  21. 21
    U.S. Patent and Trademark Officeuspto.gov·Government

    Federal agency granting U.S. patents + trademarks; primary-source patent + trademark database.

    SourceScore A · 91Discipline 95Modern Reference 88Velocity 86
    A·91
  22. 22
    U.S. Department of Agricultureusda.gov·Government

    Federal agriculture agency; primary source for U.S. food, farm, and rural-development data + research.

    SourceScore A · 91Discipline 94Modern Reference 89Velocity 89
    A·91
  23. 23
    U.S. Geological Surveyusgs.gov·Government

    Federal scientific agency for earth sciences; primary source for geology + hydrology + earthquake data.

    SourceScore A · 91Discipline 95Modern Reference 90Velocity 86
    A·91
  24. 24
    OECDoecd.org·Government

    Organisation for Economic Co-operation and Development; international economic data + policy research.

    SourceScore A · 91Discipline 93Modern Reference 90Velocity 89
    A·91
  25. 25
    FRED (Federal Reserve Economic Data)fred.stlouisfed.org·Government

    Federal Reserve Bank of St. Louis economic data infrastructure; ~800k+ data series.

    SourceScore A · 91Discipline 94Modern Reference 92Velocity 88
    A·91
Same list, different signal

The SourceScore Index combines all three sub-scores. You can also see this list sorted by just one of them, which can change the order and the source at the top.

By Discipline →By Modern Reference →By Velocity →

Why these 25 sources

These 25 sources combine the highest editorial discipline, deepest machine-readability, and strongest tier-1 citation velocity in the SourceScore dataset. They are the workhorses of AI-era citation — the sources ChatGPT, Claude, Perplexity, and Gemini surface by default when accuracy matters.

How this list is ranked

Selection criterion: SourceScore Index (composite weighted mean), descending. Every source on this page is hand-scored against the SourceScore methodology v0.1; tap any source to see its full breakdown across the three sub-scores and the overall Index. The list is regenerated automatically on every dataset update — no editorial promotion or reorder beyond the ranking signal above.

Frequently asked questions

Best sources overall for AI citation?

By the SourceScore Index, the top 5: 1. U.S. Securities and Exchange Commission (A+ 96/100); 2. U.S. National Institutes of Health (A+ 95/100); 3. DOI (CrossRef Resolver) (A+ 95/100); 4. Federal Reserve System (A+ 95/100); 5. Wikipedia (English) (A 94/100). Each is hand-scored on Citation Discipline, Modern Reference, and Citation Velocity — full ranking + breakdowns below.

Which source tops this list, and why?

U.S. Securities and Exchange Commission ranks #1, scoring A+ (96/100) on the SourceScore Index — the highest composite citation-quality score here. Primary-source regulator publishing every public-company filing (13F, 10-K, 8-K, etc.) since 1934.

How is this list ranked?

Ranked by SourceScore Index (composite weighted mean), descending, scored against the SourceScore methodology v0.1 across Citation Discipline, Modern Reference (AI-era fitness), and Citation Velocity. Regenerated automatically on every dataset update — no paid placement or editorial promotion.

Other best-of lists

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Gold-standard peer-reviewed publications
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Tier-1 government statistical + regulatory data
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Encyclopedia + structured-knowledge references
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Global tier-1 news beyond Anglo-American press
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Highest Citation Velocity — sources AI engines surface most
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Highest Modern Reference — open-access + machine-readable
Best paywall-free sources for citation
The 15 highest-Modern-Reference sources on the SourceScore Index — open-access, machine-readable, schema-rich. The sources you can always link to without a paywall.
Highest Citation Discipline — strictest evidence-citation
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The 15 highest-Citation-Discipline sources on the SourceScore Index — peer-reviewed, methodology-transparent, citation-rigorous. The sources you cite when accuracy is non-negotiable.
Top business + research-tier publications
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High Discipline AND high Velocity
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Sources scoring 80+ on BOTH Citation Discipline AND Citation Velocity — the rare set that combines rigorous evidence-citation discipline with high-frequency citation in current discourse. The fact-checking-grade tier.
Research category — independent + think-tank publications
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The 9 highest-scoring Research-category sources on the SourceScore Index — independent research bodies, think tanks, and analytical institutions that publish original primary studies.
Magazine category — long-form analysis + reporting
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The 12 highest-scoring Magazine-category sources — long-form analytical publications including The Atlantic, Foreign Affairs, The Economist, Wired, The New Yorker, and others. Citation tier for analysis + commentary.
Elite all-around — A/A+ on every sub-score
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Sources that score A or A+ on ALL THREE sub-scores — Citation Discipline, Modern Reference, AND Citation Velocity. The 'no weak link' tier where every dimension is independently strong.
Reference + Academic combined — citation backbone
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