Ranking · Winter 2026 · B2B · Engineering, Product and Design

21st

UI building blocks for the agentic internet

8.8%

odds of being acquired in the next two years

1.3× the average (6.8%)

#827 of 4,339 active YC companies · top 20%

Team of 3 · San Francisco, CA, USA

Raises the odds

↑ industry: B2B

↑ team of 3–5

↑ based in United States of America

↑ rewrote its description in the last six months

Lowers the odds

↓ under 1.5 years since YC

↓ “building” in its one-liner

From the model: how this company's profile compares with companies that were and weren't acquired since 2024. How it works.

Signals brief

ExitOdds reads 21st's website and YC profile; Contextrie keeps the passages that bear on an acquisition, and every signal quotes its source.

3 free briefs left today

21st.dev YC profile

Statistical estimate from public directory data as of 2026-10-07; it can't see revenue, funding or talks. Not investment advice. ExitOdds is independent and not affiliated with Y Combinator.

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