funding_articleMay 20, 2026Confidence: high
Our Story | 21st
Founders state they got into Y Combinator W26; no public round size on company site.
Affected score: yesObserved: May 20, 2026Round: Seed
raisedseed
2
21st
SeedFunding signalMarket data is refreshed once per day from public sources. Information may be incomplete or outdated — verify independently before making decisions. This is not investment advice.
Beta
DealFlow OS uses public web data and automated enrichment. Research may be incomplete, outdated, or incorrect. Verify important information before making investment or outreach decisions.
Investor read
Evidence-bound summary — expand sections for movement, risks, and signals.
Memo snapshot · May 20, 2026, 5:29 PM
Beta
DealFlow OS uses public web data and automated enrichment. Research may be incomplete, outdated, or incorrect. Verify important information before making investment or outreach decisions.
What they do
21st.dev provides infrastructure and UI building blocks for the agentic internet, including an AI agent registry, UI components, and developer tools to help ship AI-powered products faster.
Funding
Part of Y Combinator W26 (Medium)
Quick read
- •AI-powered product development
- •Open-source UI components
- •Agentic internet solutions
Stage
Seed (YC)
Evidence summary
Verified facts
- •21st.dev provides AI agent registry and UI components
- •They offer developer tools for the agentic internet
- •The company is part of Y Combinator W26
Inferred (corpus-only)
- •The company is likely focused on AI and UI development (interpretation of corpus)
- •Their solutions may be used for building agentic internet products (interpretation of corpus)
Recent movers
- •No specific dates mentioned in the corpus
- •No specific dates mentioned in the corpus
Funding
Part of Y Combinator W26 (Medium)
Hiring
Public jobs page available (Medium)
GitHub
No github information available (Low)
Product / news
AI agent registry and UI components available (Medium)
Traffic / social
No traffic or social metrics available (Low)
Funding & hiring signals
ReferenceFeb 11, 2026Confidence: high
Integrate raises $17M to move defense project management into the 21st century
Affected score: yesObserved: Feb 11, 2026Amount: $17M
led byraises
ReferenceOct 2, 2024Confidence: high
Pallet uses AI to bring logistics into the 21st century
Affected score: yesObserved: Oct 2, 2024Round: series a
series afunding roundled byfunding
Open roles (indexed)
No open roles indexed yet.
Failed or blocked links
No failed or blocked source links on record.
DealFlow growth score
55.0Moderate public activity signal
7D-23%
30D+0%
High Confidence
The score is an algorithmic estimate based on observed public company-level signals. It may be incomplete, stale, or inaccurate and is not investment, legal, tax, or business advice.
Source health
- public_market_enrichmentokLast checked Mon, May 11, 09:00 AM
- public_page:_pressokLast checked Mon, May 11, 09:00 AM
- public_page:_newsokLast checked Mon, May 11, 09:00 AM
- public_page:_jobsokLast checked Mon, May 11, 09:00 AM
- public_page:_homeokLast checked Mon, May 11, 09:00 AM
- public_page:_companyokLast checked Mon, May 11, 09:00 AM
- public_page:_careersokLast checked Mon, May 11, 09:00 AM
- public_page:_blogokLast checked Mon, May 11, 09:00 AM
- public_page:_aboutokLast checked Mon, May 11, 09:00 AM
- public_page:_okLast checked Mon, May 11, 09:00 AM
- public_page:homeokLast checked Mon, May 11, 09:00 AM
- public_page:customersokLast checked Sun, May 10, 11:00 PM
- public_page:pricingokLast checked Sun, May 10, 11:00 PM
- public_page:pressokLast checked Sun, May 10, 11:00 PM
- public_page:newsokLast checked Sun, May 10, 11:00 PM
- public_page:blogokLast checked Sun, May 10, 11:00 PM
- public_page:jobsokLast checked Sun, May 10, 11:00 PM
- public_page:careersokLast checked Sun, May 10, 11:00 PM
- public_page:teamokLast checked Sun, May 10, 11:00 PM
- public_page:aboutokLast checked Sun, May 10, 11:00 PM
DealFlow score momentum
557D -2330D +0
100500
More runs will build history.
The score is an algorithmic estimate based on observed public company-level signals. It may be incomplete, stale, or inaccurate and is not investment, legal, tax, or business advice.
Signal breakdown
Latest momentum signal per category. Expand a card to inspect raw payloads.
Public source summary
- Total evidence rows
- 14
- Latest evidence
- Wed, May 20, 05:29 PM
Source types found
about_pageblogcareers_pagecompany_sitefounderfunding_articlenewsofficial_sitepressproduct
Strongest / recent news-style rows
Our Story | 21st
Wed, May 20, 05:29 PM · confidence 88%high quality
https://21st.dev/our-story21st Jobs
Wed, May 20, 05:29 PM · confidence 85%high quality
https://21st.dev/community/jobsspring is here's UI components | 21st
About / company · Mon, May 11, 09:00 AM · confidence 70%high quality
https://21st.dev/community/company
Public signal timeline
Newest first · 14 event(s)
1
Wed, May 20, 05:29 PM · company_site · 85% · verified_publichigh quality
Source ↗21st.dev
Official homepage for agent registry and UI tools.
2
Wed, May 20, 05:29 PM · funding_article · 88% · verified_publichigh quality
Source ↗Our Story | 21st
Founders state they got into Y Combinator W26; no public round size on company site.
3
Wed, May 20, 05:29 PM · press · 85% · verified_publichigh quality
Source ↗21st Jobs
Public jobs/community hiring surface.
4
Mon, May 11, 09:00 AM · blog · 90% · publichigh quality
Source ↗News — 21st
Source: Blog / news
What the UI crowd is reading. Links, discussions and launches from the 21st community.
5
Mon, May 11, 09:00 AM · about_page · 70% · publichigh quality
Source ↗spring is here's UI components | 21st
Source: About / company
Browse spring is here's open-source UI components on 21st.dev.
6
Mon, May 11, 09:00 AM · blog · 90% · publichigh quality
Source ↗Blog | 21st
Source: Blog / news
Guides, agent templates, and incident reports from the 21st.dev team - learn how to build and deploy AI agents with 21st SDK and Claude Code.
7
Sun, May 10, 11:00 PM · product · 70% · publichigh quality
Source ↗21st: Infrastructure and UI building blocks for the agentic internet
Source: Customers
Ship AI-powered products faster with 21st Agents SDK, open-source UI components, and developer tools built for the agentic internet.
8
Sun, May 10, 11:00 PM · product · 70% · publichigh quality
Source ↗Discover community-made UI components | 21st
Source: Pricing
Explore, copy, and remix thousands of high-quality React components published to the 21st.dev Community by designers and developers.
9
Sun, May 10, 11:00 PM · news · 70% · publichigh quality
Source ↗21st: Infrastructure and UI building blocks for the agentic internet
Source: Press
Ship AI-powered products faster with 21st Agents SDK, open-source UI components, and developer tools built for the agentic internet.
10
Sun, May 10, 11:00 PM · news · 90% · publichigh quality
Source ↗News — 21st
Source: News
What the UI crowd is reading. Links, discussions and launches from the 21st community.
11
Sun, May 10, 11:00 PM · careers_page · 70% · publichigh quality
Source ↗21st: Infrastructure and UI building blocks for the agentic internet
Source: Careers page
Ship AI-powered products faster with 21st Agents SDK, open-source UI components, and developer tools built for the agentic internet.
12
Sun, May 10, 11:00 PM · founder · 70% · publichigh quality
Source ↗21st: Infrastructure and UI building blocks for the agentic internet
Source: Team page
Ship AI-powered products faster with 21st Agents SDK, open-source UI components, and developer tools built for the agentic internet.
13
Sun, May 10, 11:00 PM · about_page · 70% · publichigh quality
Source ↗21st: Infrastructure and UI building blocks for the agentic internet
Source: About page
Ship AI-powered products faster with 21st Agents SDK, open-source UI components, and developer tools built for the agentic internet.
14
Sun, May 10, 11:00 PM · official_site · 90% · publichigh quality
Source ↗21st.dev — AI Agent Registry, UI Components & Developer Tools for the Agentic Internet
Source: Homepage
Ship AI-powered products faster with 21st.dev. Browse the open AI agent registry, discover ready-to-use agent configs for Claude Managed Agents, copy React UI components, and build with the Agents SDK.
Official / company site
2 row(s)
company_site·Wed, May 20, 05:29 PM·Confidence 85%high qualityverified_public
21st.dev
Official homepage for agent registry and UI tools.
https://21st.dev/homeofficial_site·Sun, May 10, 11:00 PM·Confidence 90%high qualitypublic
21st.dev — AI Agent Registry, UI Components & Developer Tools for the Agentic Internet
Source name: Homepage
Ship AI-powered products faster with 21st.dev. Browse the open AI agent registry, discover ready-to-use agent configs for Claude Managed Agents, copy React UI components, and build with the Agents SDK.
https://21st.dev/homeNews
8 row(s)
press·Wed, May 20, 05:29 PM·Confidence 85%high qualityverified_public
21st Jobs
Public jobs/community hiring surface.
https://21st.dev/community/jobsabout_page·Mon, May 11, 09:00 AM·Confidence 70%high qualitypublic
spring is here's UI components | 21st
Source name: About / company
Browse spring is here's open-source UI components on 21st.dev.
https://21st.dev/community/companyproduct·Sun, May 10, 11:00 PM·Confidence 70%high qualitypublic
21st: Infrastructure and UI building blocks for the agentic internet
Source name: Customers
Ship AI-powered products faster with 21st Agents SDK, open-source UI components, and developer tools built for the agentic internet.
https://21st.dev/community/customersproduct·Sun, May 10, 11:00 PM·Confidence 70%high qualitypublic
Discover community-made UI components | 21st
Source name: Pricing
Explore, copy, and remix thousands of high-quality React components published to the 21st.dev Community by designers and developers.
https://21st.dev/community/componentsnews·Sun, May 10, 11:00 PM·Confidence 70%high qualitypublic
21st: Infrastructure and UI building blocks for the agentic internet
Source name: Press
Ship AI-powered products faster with 21st Agents SDK, open-source UI components, and developer tools built for the agentic internet.
https://21st.dev/community/pressnews·Sun, May 10, 11:00 PM·Confidence 90%high qualitypublic
News — 21st
Source name: News
What the UI crowd is reading. Links, discussions and launches from the 21st community.
https://21st.dev/newsfounder·Sun, May 10, 11:00 PM·Confidence 70%high qualitypublic
21st: Infrastructure and UI building blocks for the agentic internet
Source name: Team page
Ship AI-powered products faster with 21st Agents SDK, open-source UI components, and developer tools built for the agentic internet.
https://21st.dev/sign-in?redirect_url=%2Fteamabout_page·Sun, May 10, 11:00 PM·Confidence 70%high qualitypublic
21st: Infrastructure and UI building blocks for the agentic internet
Source name: About page
Ship AI-powered products faster with 21st Agents SDK, open-source UI components, and developer tools built for the agentic internet.
https://21st.dev/community/aboutFunding / news
1 row(s)
funding_article·Wed, May 20, 05:29 PM·Confidence 88%high qualityverified_public
Our Story | 21st
Founders state they got into Y Combinator W26; no public round size on company site.
https://21st.dev/our-storyHiring
1 row(s)
careers_page·Sun, May 10, 11:00 PM·Confidence 70%high qualitypublic
21st: Infrastructure and UI building blocks for the agentic internet
Source name: Careers page
Ship AI-powered products faster with 21st Agents SDK, open-source UI components, and developer tools built for the agentic internet.
https://21st.dev/community/careersBlog
2 row(s)
blog·Mon, May 11, 09:00 AM·Confidence 90%high qualitypublic
News — 21st
Source name: Blog / news
What the UI crowd is reading. Links, discussions and launches from the 21st community.
https://21st.dev/newsblog·Mon, May 11, 09:00 AM·Confidence 90%high qualitypublic
Blog | 21st
Source name: Blog / news
Guides, agent templates, and incident reports from the 21st.dev team - learn how to build and deploy AI agents with 21st SDK and Claude Code.
https://21st.dev/community/blogPrivate workspace
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