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S25 companies that raised the most in the last 12 months

The 27 YC S25 companies whose latest reported round, after their YC batch and in the last 12 months, was the largest.

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

Showing 27 of 27 companies on this list
#CompanyTeam6 mo12 moOpen rolesTotal raisedLast round
1
AI that makes AI fast
18+200% 2$44.8MSeries A$40M, Sep 2026
2
Data and RL environments to automate knowledge work
55  2$30.5MSeries A$30M, Oct 2026
3
Making AI run fast on any hardware.
13+18%+44%YC$35MUndisclosed round$29.2M, Oct 2026
4
We Bring Customers to Your Dealership
35+94%+289%15$33.5MSeries A$27M, Oct 2026
5
Supplying America's Industrial Base
35+218%+600%YC$16.8MSeed$11.5M, Jun 2026
6
Hill-climb any benchmark, for any model, in any domain.
16+7%+129%2$9.5MSeed$9M, Aug 2026
7
RNA intelligence for precision medicine
8  0$7.3MSeed$7.2M, May 2026
8
Cloud infrastructure for MCP servers and Claude / ChatGPT plugins.
5  YC$6.8MSeed$6.3M, Feb 2026
9
Email Inboxes for AI Agents
13+30% 3$6.5MSeed$6M, Mar 2026
10
Database of every product on the internet
9+50% YC$6.5MSeed$6M, Dec 2025
11
Building the new superintelligence for insurance
140%+40%YC$6MSeed$6M, Aug 2026
12
Agentic sales enrichment spreadsheet
9−31%−25%YC$5.8MSeed$5.3M, Feb 2026
13
AI Tax Preparer for CPA firms
9+29% YC$5.7MSeed$5.2M, Jun 2026
14
Your personal investing agent
7−12%+17%0$5.5MSeed$5M, Apr 2026
15
The AI platform for private markets investors
38+90%+81%6$29MSeed$5M, Sep 2026
16
The Global Dollar App for Brazil
31+24%+63%0$5.1MSeed$4.6M, Feb 2026
17
AI agents that automate administrative work across college campuses.
9+50%+29%0$4.1MSeed$3.6M, May 2026
18
AI Agents for E-commerce Customer Support
8+60% 0$4.1MSeed$3.6M, Mar 2026
19
The open-source platform that continuously improves your ai agents
7  YC$3.5MSeed$3.5M, Jun 2026
20
Your personal AI Assistant
14−7%−7%2$5.2MSeed$3.5M, Aug 2026
21
Foundational Voice Models for regional languages
60%−14%YC$4MSeed$3.5M, Jan 2026
22
AI accounting for enterprise finance teams
13+63% 1$3.4MSeed$3.4M, Jul 2026
23
AI Native Rippling for Deskless Workers
10+67% YC$3.9MSeed$3.4M, Nov 2025
24
Context-aware orchestration between humans and AI.
50% 0$3.5MSeed$3M, Feb 2026
25
Production infrastructure on autopilot
6+20% 0$3.5MSeed$3M, Jan 2026
26
AI agents for E2E testing across mobile & web
8 +60%0$3.2MSeed$2.7M, Feb 2026
27
Deep research for class action law firms
3  YC$1.2MSeed$692K, Apr 2026

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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