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YC S25 companies (Summer 2025)

All 165 companies in Y Combinator's Summer 2025 batch, with team size, growth, open roles and funding.

Updated weekly, last on November 9, 2026. Roster from Y Combinator's public directory.

Hiring the mostlast 60 days
15 roles
FlaiS25
  1. 2F26
  2. 3Comena5
See all 14
Fastest growingteam, 6 months
+355%
FreyaS25
  1. 2Nox Metals+218%
  2. 3Wafer+200%
See all 33
Raised the mostlast 12 months
$40M
WaferS25
  1. 2Halluminate$30M
  2. 3Luminal$29.2M
See all 27
Companies
165
Active
158
Hiring, last 60 days
14
Open roles, 60 days
48
People on these teams
1,671
Showing 50 of 165 companies
CompanyTeam6 mo12 moOpen rolesTotal raisedLast round
Infrastructure to build reliable agents
74+722%+573%0$500KYC investment$500K, Sep 2025
Voice AI for Enterprises
50+355%+900%YC$4MGrant$3.5M, Jul 2026
The AI platform for private markets investors
38+90%+81%6$29MSeed$5M, Sep 2026
We Bring Customers to Your Dealership
35+94%+289%15$33.5MSeries A$27M, Oct 2026
Drone submarines
35+30%+59%0$6.5MSeed$6.5M, Sep 2025
Supplying America's Industrial Base
35+218%+600%YC$16.8MSeed$11.5M, Jun 2026
Your personal AI for language learning
33+14%+83%0$500KYC investment$500K, Sep 2025
We automate creator marketing for the world's largest brands
33+38%+57%YC$500KYC investment$500K, Sep 2025
The Global Dollar App for Brazil
31+24%+63%0$5.1MSeed$4.6M, Feb 2026
Automation Foundation Models For Tiny Devices
24−14%+167%0$500KYC investment$500K, Jan 2026
Crazy fast, open source infra for AI agents to use the Internet
24+33%+167%0$22.6MSeries A$16M, Oct 2025
AI agents for the consumer lending industry
22+29%+144%3SeedSep 2025
Secure frontier AI for government & adjacent knowledge work
21+110%+250%YC$10.9MSeed$10.9M, Oct 2025
We help products get discovered & used by AI agents.
20+18%+43%YC$7MSeed$6.5M, Oct 2025
AI that makes AI fast
18+200% 2$44.8MSeries A$40M, Sep 2026
Cursor for Email
18 +13%0$550KPre-seed$550K, Sep 2025
Hill-climb any benchmark, for any model, in any domain.
16+7%+129%2$9.5MSeed$9M, Aug 2026
Persistent computers for AI agents
15−25%+15%1$11.5MSeed$11M, Oct 2025
Book any load in 10 minutes
14+40%+56%YC$500KYC investment$500K, Jan 2026
AI video editor
14−12% 0$500KYC investment$500K, Sep 2025
Building the new superintelligence for insurance
140%+40%YC$6MSeed$6M, Aug 2026
Your personal AI Assistant
14−7%−7%2$5.2MSeed$3.5M, Aug 2026
The Cross-Border Neobank for the Middle East
14+17%+40%0$3MSeed$3M, Aug 2025
Email Inboxes for AI Agents
13+30% 3$6.5MSeed$6M, Mar 2026
AI agents for distributors and manufacturers to automate order entry.
13+30% 5$500KYC investment$500K, Sep 2025
creators of folk.com
13+86%+117%YC$8.2MSeed$6.2M, Oct 2025
AI accounting for enterprise finance teams
13+63% 1$3.4MSeed$3.4M, Jul 2026
Done-for-you AI video paid ads and Meta campaign management
13−7%+18%0
The world's first AI-maximalist pharma company
13  0$500KYC investment$500K, Sep 2025
Making AI run fast on any hardware.
13+18%+44%YC$35MUndisclosed round$29.2M, Oct 2026
Autonomous Firmware Engineer
12−8%+71%0$500KYC investment$500K, Jan 2026
The app platform inside Claude and ChatGPT.
12+71% YC$500KYC investment$500K, Jul 2025
Voice AI Agents for Debt Collection
12+50%+71%YC$600KYC investment$500K, Sep 2025
AI rebuilt coding. We’re rebuilding the phone
12−14%+9%YC$500KYC investment$500K, Sep 2025
AI voice for property managers
11  YC$500KYC investment$500K, Sep 2025
AI models that teach robots new skills in hours
11+83% YC$500KYC investment$500K, Sep 2025
America's Golden Dome for Drones
11+38% YC$6.5MSeed$6M, Sep 2025
The AI data analyst for biology labs
11+83%+83%YC$500KYC investment$500K, Jul 2025
Replacing the restaurant phone line with Voice AI
11+22%+38%0$500KYC investment$500K, Sep 2025
Reshoring critical metal production
11+38% 0$500KYC investment$500K, Sep 2025
AGI for home service
11+83% YC$500KYC investment$500K, Sep 2025
World's largest crowdsourced benchmark for AI-generated design
10+100% 0$500KYC investment$500K, Sep 2025
Consumer focus groups run by AI
10+25%+11%0$500KYC investment$500K, Sep 2025
AI Native Rippling for Deskless Workers
10+67% YC$3.9MSeed$3.4M, Nov 2025
Optimizing fleet planning with data driven algorithms
10+100% YC$500KYC investment$500K, Sep 2025
Building socially intelligent AI
9−31%+50%0$3MSeed$3M, Sep 2025
Build and ship native Swift apps with AI
9+29% 0
Agentic sales enrichment spreadsheet
9−31%−25%YC$5.8MSeed$5.3M, Feb 2026
AI Employees for Healthcare
9+13%−44%YC$500KYC investment$500K, Sep 2025
Database of every product on the internet
9+50% YC$6.5MSeed$6M, Dec 2025

How this works

1. The roster

Every launched company in YC's public directory, with its batch, status, industry and location. New companies show up the week YC lists them.

2. The numbers

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.

3. The lists

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.

Built with Crustdata. Get your own API key and build your own.

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.

  • Company search for team size, growth and funding
  • Job search with a count by company, for who is hiring and for what
  • A watch that re-runs the search weekly and sends only what changed
# 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

Questions about YC S25 companies

How many YC S25 companies are there?

165 companies were in Y Combinator's Summer 2025 batch (S25); 158 are active.

Which YC S25 companies are hiring?

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.

Which YC S25 companies are growing fastest?

By team growth over 6 months (10+ people): Freya (+355%), Nox Metals (+218%) and Wafer (+200%).

Which YC S25 companies raised the most?

Largest latest rounds in the last 12 months, after their YC batch: Wafer ($40M), Halluminate ($30M) and Luminal ($29.2M).

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