The 43 YC W25 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 | The data layer for perceptual intelligence | 44 | +300% | +450% | 2 | $24M | Series A$20M, Aug 2026 |
| 2 | Frontier Video Agents | 13 | +117% | +117% | YC | $500K | YC investment$500K, Mar 2025 |
| 3 | AI-native ATS/CRM for recruiting firms | 47 | +96% | +327% | 2 | $24.2M | Series A$21M, Sep 2026 |
| 4 | The OS for hospital workforce management | 17 | +70% | +240% | YC | $500K | YC investment$500K, Mar 2025 |
| 5 | Foundational model of human societies for consequential decisions | 22 | +69% | +120% | 0 | $5.1M | Seed$3.3M, Aug 2025 |
| 6 | AI tutors for exam prep | 10 | +67% | YC | $500K | YC investment$500K, Mar 2025 | |
| 7 | AI compliance co-pilot for regulated financial businesses | 16 | +60% | 0 | SeedMar 2025 | ||
| 8 | Applied research lab curating data solutions for foundation model… | 286 | +58% | +186% | 25 | $30.5M | Series B$30M, Sep 2026 |
| 9 | Ergo is the context layer that helps revenue teams close more deals. | 11 | +57% | +83% | YC | $3.3M | Seed$2.8M, Jun 2026 |
| 10 | High Thrust Space Vehicles for Satellite Defense | 26 | +53% | +117% | 1 | $8.8M | Seed$8.8M, Aug 2025 |
| 11 | AI agents for CX teams, starting with training and QA. | 43 | +48% | +187% | 2 | $32.7M | Series A$25M, Apr 2026 |
| 12 | AI Accountant for Accounting Firms | 16 | +45% | +129% | YC | $1.5M | Seed$1M, Mar 2026 |
| 13 | Making humanoids dexterous enough to thread a needle | 17 | +42% | +31% | YC | $11M | Seed$11M, Jun 2026 |
| 14 | AI-native commercial insurance brokerage | 85 | +35% | +158% | 14 | $47.5M | Series A$47M, Feb 2026 |
| 15 | AI-powered student information system for K-12 schools | 16 | +33% | +100% | YC | $500K | YC investment$500K, Mar 2025 |
| 16 | AI to understand and then route engineering work | 25 | +32% | +127% | 2 | $18.2M | Series A$13.5M, Jul 2026 |
| 17 | Query mission-critical video | 22 | +29% | +69% | 0 | $14.4M | Seed$7M, Mar 2026 |
| 18 | AI estimating & detailing for Division 8 doors, frames & hardware | 10 | +25% | +67% | 1 | $3.6M | Seed$3.1M, Jul 2025 |
| 19 | AI tutor starting with maths and science | 10 | +25% | −9% | 0 | $500K | YC investment$500K, Jan 2026 |
| 20 | Autonomous patrol-boats for National Security | 10 | +25% | +43% | YC | $4.7M | Seed$4.2M, Jul 2026 |
| 21 | Manufacturing the most powerful chips, 15x faster | 10 | +25% | +25% | 0 | $500K | YC investment$500K, Jan 2026 |
| 22 | AI-powered Patient Identification for Clinical Trials | 12 | +20% | +33% | YC | $500K | YC investment$500K, Jan 2026 |
| 23 | Agentic Sales Platform | 12 | +20% | +50% | YC | $500K | YC investment$500K, Mar 2025 |
| 24 | The Javascript framework for building AI agents, from the Gatsby devs | 62 | +19% | +44% | 0 | $35M | Series A$22M, Apr 2026 |
| 25 | Supply chain superintelligence for distribution and procurement | 26 | +18% | +37% | 3 | $5.5M | Seed$5M, Oct 2025 |
| 26 | We help law enforcement solve crime | 13 | +18% | +160% | YC | $7M | Seed$7M, Mar 2025 |
| 27 | Global B2B Stablecoin Processor | 20 | +18% | +43% | 2 | ||
| 28 | awen translates intent into exceptional visuals through conversation | 14 | +17% | +75% | 0 | $500K | YC investment$500K, Mar 2025 |
| 29 | AI quote & order processing for technical distributors & manufacturers | 24 | +14% | +4% | YC | $2.6M | Seed$2.1M, Dec 2025 |
| 30 | AI Teacher Assistant for Grading Essays | 17 | +13% | YC | $600K | Seed$600K, Jan 2025 | |
| 31 | AI hiring platform powered by expert recruiters | 62 | +13% | +130% | 0 | $2.8M | Seed$2.3M, May 2026 |
| 32 | Be the Answer in AI Search - AI SEO across SEO, GEO & AEO | 20 | +11% | +18% | YC | $2.7M | Seed$2.2M, Mar 2025 |
| 33 | Open Source React.js Library for AI Chat | 10 | +11% | +11% | 0 | $500K | YC investment$500K, Mar 2025 |
| 34 | AI systems for aviation | 22 | +10% | +29% | 0 | $500K | YC investment$500K, Mar 2025 |
| 35 | Production Monitoring & Evals for AI Agents | 11 | +10% | +38% | YC | $2.2M | Seed$2.2M, Mar 2025 |
| 36 | AI for insurance verification & billing at dental clinics | 12 | +9% | YC | SeedMar 2025 | ||
| 37 | Stablecoin API for global payments | 12 | +9% | +20% | 0 | $3.8M | Seed$3.3M, Aug 2025 |
| 38 | AI Powered CAD | 15 | +7% | +50% | YC | $4.6M | Seed$4.1M, Oct 2025 |
| 39 | Agents for Accelerated Clinical Trial Design | 32 | +7% | +19% | 0 | $500K | YC investment$500K, May 2025 |
| 40 | AI voice and texting agents | 16 | +7% | +60% | 1 | $5.2M | Seed$4.7M, Mar 2025 |
| 41 | Platform and marketplace for RL environments and AI data | 16 | +7% | +23% | YC | $16.2M | Series A$14M, Jun 2026 |
| 42 | Software Enabled CNC Parts Supplier | 17 | +6% | +113% | YC | $500K | YC investment$500K, Mar 2025 |
| 43 | AI-driven exam prep | 21 | +5% | 0 | $5.2M | Seed$4.7M, May 2025 |
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
166 companies were in Y Combinator's Winter 2025 batch (W25); 159 are active.
15 companies posted roles in the last 60 days, led by AfterQuery (25 roles), Harper (14 roles) and SalesPatriot (3 roles). 66 mark themselves as hiring on YC's directory.
By team growth over 6 months (10+ people): Mundo AI (+300%), Mosaic (+117%) and Spott (+96%).
Largest latest rounds in the last 12 months, after their YC batch: Harper ($47M), AfterQuery ($30M) and Solidroad ($25M).