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ChatGPT Custom GPTs Marketplace

OpenAI's GPT Store turned ChatGPT into a platform. More than 3 million custom GPTs have been created since the feature launched in late 2023, though only about 159,000 are publicly listed in the Store — most are built privately for personal or internal company use. Custom GPTs now account for roughly 12% of daily ChatGPT usage and about 20% of enterprise messages, and structured workflows like Projects and Custom GPTs grew nearly 19x inside enterprises during 2025. This page tracks how big the catalog is, how much usage runs through custom GPTs, and where developer activity is concentrated.

4 visualizations 5 sources Last updated June 2026 Free to embed
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Source: OpenAI (3M+ created, via Wikipedia); SEO.ai (~159K public in the Store). Most GPTs are private or unlisted.
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Chart 1 · Catalog size

Custom GPTs created vs publicly listed

Custom GPTs: created vs publicly listed

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Source: OpenAI (via Wikipedia): 3M+ custom GPTs created; SEO.ai analysis: ~159,000 public GPTs in the Store. The vast majority of GPTs are private or unlisted; the public Store is a small, curated slice of everything built.
Chart 2 · Share of usage

Custom GPTs as a share of activity

Share of activity via Custom GPTs

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Source: SQ Magazine (Custom GPTs ~12% of daily usage); Master of Code / OpenAI enterprise report (~20% of enterprise messages via Custom GPTs or Projects). Custom GPTs are used more heavily inside enterprises than in general consumer usage.
Chart 3 · Enterprise momentum

Custom GPTs usage growth in 2025

Enterprise Custom GPTs / Projects growth (2025, indexed)

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Source: OpenAI enterprise report (via Panto): structured workflows such as Projects and Custom GPTs grew ~19x year to date in 2025. A single enterprise (BBVA) runs 4,000+ custom GPTs. Index shown as relative growth (start of 2025 = 1x).
Chart 4 · What gets built

Public GPTs by Store category

Public GPT Store composition by category (illustrative)

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Source: SEO.ai, GPT Store category structure (8 categories: Writing, Productivity, Research & Analysis, Programming, Education, Lifestyle, DALL·E, Top Picks). Category distribution is illustrative of the Store's composition; OpenAI does not publish exact per-category counts.

About this data

This page compiles published data on OpenAI's GPT Store and custom GPTs, drawing on OpenAI's own disclosures (as catalogued by Wikipedia), OpenAI's 2025–2026 enterprise report (via secondary coverage), and third-party analyses from SEO.ai, SQ Magazine, and Master of Code.

The AI Behavior Index is the research arm of OneChat AI, an integrated multi-model AI platform. We compile and analyze data from primary research sources to make AI adoption and market trends more accessible to journalists, researchers, and decision-makers.

Why "3 million" and "159,000" are both right: 3 million+ is the number of custom GPTs created (most are private, unlisted, or for internal company use); ~159,000 is the number publicly listed in the GPT Store. They count different populations. Usage-share figures (12% of daily usage, 20% of enterprise messages) come from different studies with different denominators and should be read as approximate.

Methodology notes: creation counts are OpenAI disclosures; public-Store counts are third-party crawls and move over time. The 19x enterprise-growth figure is a year-to-date relative measure from OpenAI's enterprise report, shown here as an index (start of 2025 = 1x), not absolute volume. The category-distribution chart reflects the Store's 8-category structure and is illustrative of composition — OpenAI does not publish exact per-category GPT counts.

Sources used on this page:

Corrections or suggestions: research@aibehaviorindex.org

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