The 33 YC S25 companies whose team grew the most in the last 6 months (active companies with 10+ people).
Updated weekly, last on November 9, 2026. Roster from Y Combinator's public directory.
| # | Company | Team | 6 mo | 12 mo | Open roles | Total raised | Last round |
|---|---|---|---|---|---|---|---|
| 1 | Voice AI for Enterprises | 50 | +355% | +900% | YC | $4M | Grant$3.5M, Jul 2026 |
| 2 | Supplying America's Industrial Base | 35 | +218% | +600% | YC | $16.8M | Seed$11.5M, Jun 2026 |
| 3 | AI that makes AI fast | 18 | +200% | 2 | $44.8M | Series A$40M, Sep 2026 | |
| 4 | Secure frontier AI for government & adjacent knowledge work | 21 | +110% | +250% | YC | $10.9M | Seed$10.9M, Oct 2025 |
| 5 | World's largest crowdsourced benchmark for AI-generated design | 10 | +100% | 0 | $500K | YC investment$500K, Sep 2025 | |
| 6 | Optimizing fleet planning with data driven algorithms | 10 | +100% | YC | $500K | YC investment$500K, Sep 2025 | |
| 7 | We Bring Customers to Your Dealership | 35 | +94% | +289% | 15 | $33.5M | Series A$27M, Oct 2026 |
| 8 | The AI platform for private markets investors | 38 | +90% | +81% | 6 | $29M | Seed$5M, Sep 2026 |
| 9 | creators of folk.com | 13 | +86% | +117% | YC | $8.2M | Seed$6.2M, Oct 2025 |
| 10 | AI models that teach robots new skills in hours | 11 | +83% | YC | $500K | YC investment$500K, Sep 2025 | |
| 11 | The AI data analyst for biology labs | 11 | +83% | +83% | YC | $500K | YC investment$500K, Jul 2025 |
| 12 | AGI for home service | 11 | +83% | YC | $500K | YC investment$500K, Sep 2025 | |
| 13 | The app platform inside Claude and ChatGPT. | 12 | +71% | YC | $500K | YC investment$500K, Jul 2025 | |
| 14 | AI Native Rippling for Deskless Workers | 10 | +67% | YC | $3.9M | Seed$3.4M, Nov 2025 | |
| 15 | AI accounting for enterprise finance teams | 13 | +63% | 1 | $3.4M | Seed$3.4M, Jul 2026 | |
| 16 | Voice AI Agents for Debt Collection | 12 | +50% | +71% | YC | $600K | YC investment$500K, Sep 2025 |
| 17 | Book any load in 10 minutes | 14 | +40% | +56% | YC | $500K | YC investment$500K, Jan 2026 |
| 18 | We automate creator marketing for the world's largest brands | 33 | +38% | +57% | YC | $500K | YC investment$500K, Sep 2025 |
| 19 | America's Golden Dome for Drones | 11 | +38% | YC | $6.5M | Seed$6M, Sep 2025 | |
| 20 | Reshoring critical metal production | 11 | +38% | 0 | $500K | YC investment$500K, Sep 2025 | |
| 21 | Crazy fast, open source infra for AI agents to use the Internet | 24 | +33% | +167% | 0 | $22.6M | Series A$16M, Oct 2025 |
| 22 | Email Inboxes for AI Agents | 13 | +30% | 3 | $6.5M | Seed$6M, Mar 2026 | |
| 23 | AI agents for distributors and manufacturers to automate order entry. | 13 | +30% | 5 | $500K | YC investment$500K, Sep 2025 | |
| 24 | Drone submarines | 35 | +30% | +59% | 0 | $6.5M | Seed$6.5M, Sep 2025 |
| 25 | AI agents for the consumer lending industry | 22 | +29% | +144% | 3 | SeedSep 2025 | |
| 26 | Consumer focus groups run by AI | 10 | +25% | +11% | 0 | $500K | YC investment$500K, Sep 2025 |
| 27 | The Global Dollar App for Brazil | 31 | +24% | +63% | 0 | $5.1M | Seed$4.6M, Feb 2026 |
| 28 | Replacing the restaurant phone line with Voice AI | 11 | +22% | +38% | 0 | $500K | YC investment$500K, Sep 2025 |
| 29 | Making AI run fast on any hardware. | 13 | +18% | +44% | YC | $35M | Undisclosed round$29.2M, Oct 2026 |
| 30 | We help products get discovered & used by AI agents. | 20 | +18% | +43% | YC | $7M | Seed$6.5M, Oct 2025 |
| 31 | The Cross-Border Neobank for the Middle East | 14 | +17% | +40% | 0 | $3M | Seed$3M, Aug 2025 |
| 32 | Your personal AI for language learning | 33 | +14% | +83% | 0 | $500K | YC investment$500K, Sep 2025 |
| 33 | Hill-climb any benchmark, for any model, in any domain. | 16 | +7% | +129% | 2 | $9.5M | Seed$9M, Aug 2026 |
Every launched company in YC's public directory, with its batch, status, industry and location. New companies show up the week YC lists them.
Each company is matched to Crustdata by its website. Crustdata adds team size and its change over 6 and 12 months, open roles from job postings, reported funding, and founders' past employers.
Hiring the most counts distinct roles posted in the last 60 days. Growth needs 10+ people today, shrinking 20+ a year ago, so tiny teams do not top the lists. Rebuilt every week.
The numbers on this page come from three Crustdata API calls. Crustdata tags 5,000+ companies with Y Combinator as an investor; swap the filter for any investor, industry or headcount range and track your own list, with founders' work emails one call away.
# 1. every company with Y Combinator as an investor curl https://api.crustdata.com/company/search \ -H "authorization: Bearer $CRUSTDATA_API_KEY" \ -H "x-api-version: 2025-11-01" \ -d '{ "filters": { "field": "funding.investors", "type": "in", "value": ["Y Combinator"] }, "fields": ["basic_info.name", "headcount.total", "headcount.growth_percent", "funding.total_investment_usd"], "limit": 100 }' # 2. open listings per company, last 60 days (limit 0 = counts only) curl https://api.crustdata.com/job/search \ -H "authorization: Bearer $CRUSTDATA_API_KEY" \ -H "x-api-version: 2025-11-01" \ -d '{ "filters": { "op": "and", "conditions": [ { "field": "company.basic_info.company_id", "type": "in", "value": [...] }, { "field": "metadata.date_added", "type": "=>", "value": "2026-08-24" } ]}, "limit": 0, "aggregations": [{ "type": "group_by", "field": "company.basic_info.company_id", "agg": "count" }] }' # 3. the same company filter as a weekly watch: POST /watch/company/search
165 companies were in Y Combinator's Summer 2025 batch (S25); 158 are active.
14 companies posted roles in the last 60 days, led by Flai (15 roles), F2 (6 roles) and Comena (5 roles). 69 mark themselves as hiring on YC's directory.
By team growth over 6 months (10+ people): Freya (+355%), Nox Metals (+218%) and Wafer (+200%).
Largest latest rounds in the last 12 months, after their YC batch: Wafer ($40M), Halluminate ($30M) and Luminal ($29.2M).