Crossref

Monthly works registered with Crossref by DOI-creation date since 2015: the all-works baseline, AI title slices and their share, named models, preprints, retraction notices, and AI vocabulary counts.

We count a work in the month a publisher registered its DOI with Crossref, not in the month of publication.

cadence · monthly 12 series updated 21 Oct 2026 www.crossref.org ↗

release markers

All works

1.2M +18.6% yr as of Sep 2026

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Publishers sometimes register many old works at once, so one month can jump high and the share lines dip that month.

AI title share

Crossref's title search ignores the quotes, so it also finds titles with only one of the two words. These counts are too high, so read the growth and not the total.

"artificial intelligence" in title

13.3k +47.6% yr as of Sep 2026

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Named models

ChatGPT in title

592 −20.2% yr as of Sep 2026

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DeepSeek in title

66 −42.6% yr as of Sep 2026

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Copilot in title

34 −24.4% yr as of Sep 2026

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This line mixes GitHub Copilot with Microsoft 365 Copilot.

Grok in title

7 −22.2% yr as of Sep 2026

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About 10 works a month. Read presence and absence, not the month-to-month movement.

Publication type

Preprints

86.0k +69.2% yr as of Sep 2026

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Preprints with a DOI from Crossref — bioRxiv, SSRN, Research Square. arXiv registers its DOIs with DataCite, so this line does not count arXiv.

Preprint share of all works derived

7.3% of works +42.7% yr as of Sep 2026

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Preprints ÷ all works, so this is the preprint share of everything with a Crossref DOI.

Research integrity

Retraction notices

298 −32.6% yr as of Sep 2026

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This line counts retraction notices in the month the publisher registered the notice. A notice from 2026 can retract a paper from 2014.

Retraction notices per 100k works derived

25.4 −43.1% yr as of Sep 2026

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Notices this month ÷ new DOIs this month × 100k. ⚠ The notices are about older papers, so this is not the share of papers that publishers retract.

AI vocabulary

LLM in title

2.0k +135.0% yr as of Sep 2026

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"transformer" in title

2.2k +14.7% yr as of Sep 2026

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⚠ This search also finds electrical power transformers — 147 works in June 2018, before the AI sense of the word. Only the growth is about AI.

Figures

Crossref: latest figure, change, range and coverage of each series
Series	Latest	Change	Min	Max	Coverage
All works	1.2M	+18.6% yr	468k	2.6M	Jan 2015 — Sep 2026
"artificial intelligence" in title	13.3k	+47.6% yr	824	14.2k	Jan 2015 — Sep 2026
ChatGPT in title	592	−20.2% yr	0	809	Jan 2015 — Sep 2026
Preprints	86.0k	+69.2% yr	428	247k	Jan 2015 — Sep 2026
Retraction notices	298	−32.6% yr	110	2.7k	Jan 2015 — Sep 2026
LLM in title	2.0k	+135.0% yr	0	3.0k	Jan 2015 — Sep 2026
"transformer" in title	2.2k	+14.7% yr	82	2.7k	Jan 2015 — Sep 2026
DeepSeek in title	66	−42.6% yr	0	115	Jan 2015 — Sep 2026
Copilot in title	34	−24.4% yr	0	48	Jan 2015 — Sep 2026
Grok in title	7	−22.2% yr	0	17	Jan 2015 — Sep 2026
Preprint share of all works	7.3%	+42.7% yr	0.071%	22.8%	Jan 2015 — Sep 2026
Retraction notices per 100k works	25.4	−43.1% yr	16.7	261.3	Jan 2015 — Sep 2026

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