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Fastest growing W19 companies

The 38 YC W19 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.

Showing 38 of 38 companies on this list
#CompanyTeam6 mo12 moOpen rolesTotal raisedLast round
1
AI agent that saves you money on travel
48+71%+200%1
2
Outbound AI Agents for Education, Insurance, and Travel
32+45%+68%0SeedJan 2019
3
All-in-one recruiting platform that empowers hiring excellence in…
580+31%+73%56$120MSeries D$50M, Jul 2025
4
Reshaping industrial quality with AI, hardware, and software
91+30%+63%24$13.3MSeries A$10M, Feb 2022
5
The phone that gives families peace of mind about aging parents
265+29%+66%8$150KUndisclosed round$150K, Nov 2023
6
Patient Intelligence Platform for Genetic Disease
28+27%+4%6$10.9MUndisclosed round$10.7M, Nov 2023
7
Bunkerhill is a long-horizon agent for health systems
33+22%+3%4$55MSeries B$25M, Jul 2026
8
API-first stock and crypto brokerage platform
525+20%+47%46$764MDebt$135M, Jul 2026
9
Non-profit building open-source voting machines for US elections.
31+19%+29%0SeedMar 2019
10
1st federally regulated exchange where people can trade on events
604+17%+83%YC$2.9BUndisclosed round$30M, Jul 2026
11
Frozen beauty products.
15+15%+25%0$1.1MUndisclosed round$1M, Aug 2019
12
Nabis is the largest licensed cannabis wholesale platform.
264+15%+27%6$59MDebt$4M, Jan 2026
13
Heart makes electric airplanes with an all-electric range of 250 miles
89+14%+24%2$151MGrant$4.1M, Sep 2024
14
We make it easier for B2B companies to transact with one another
165+11%+11%5$77MSeries B$57M, Jun 2022
15
Encarte is building 1-click checkout for all online stores.
11+10%+38%0$75KUndisclosed round$75K, Aug 2022
16
The global community for the South Asia-curious
23+10%+35%YC$2.1MSeed$2M, Aug 2022
17
Intercom for WeChat, help companies to acquire, engage, retain…
12+9%+9%YC
18
Design system platform joins developers and designers together
79+8%+20%0$25.8MSeries A$9.2M, Sep 2025
19
Healthy packaged fresh food
28+8%+12%0$7MUndisclosed round$7M, Jan 2024
20
E-signatures with identity verification for Latin America
15+7%+15%0$1.4MSeed$1.2M, Apr 2019
21
Shef is a Marketplace for Homemade Food
451+7%+11%0$109MSeries B$73.5M, Mar 2023
22
Helping creators monetize
47+7%−8%0SeedJan 2022
23
Brain Longevity
16+7%−6%0$200KConvertible note$200K, Dec 2021
24
Intuitive, easy-to-remember short links - powered by AI.
50+6%+11%1$27MSeries A$27M, Feb 2022
25
Enabling better self care with at-home hormone tracking.
264+6%+10%YC$57.5MSeries B$29M, Dec 2025
26
Enabling health professionals to prescribe clinical-grade wellness…
92+6%+12%YC$10.3MSeed$5.8M, Sep 2021
27
build AI NPCs
40+5%+5%0$26.2MUndisclosed round$500K, Feb 2023
28
Building the first sensor enabled marketplace for repeat purchases
20+5%+11%0$6.8MSeries A$4.5M, Jan 2021
29
We Create Superior Data By Making Annotation Competitive
81+5%+9%YC$35.4MSeries B$16.2M, Oct 2024
30
The Future of Supply Chain Data Tracking and Visibility
22+5%+16%0$16.8MSeries A$10.4M, Nov 2025
31
Building Payments for the Next Billion.
267+5%+9%0$75.2MDebt$25M, May 2026
32
Helping great teams hire better frontline workers, faster.
70+4%−1%0$13MSeries A$11M, Feb 2022
33
ThriveAgric help Farmers in Africa access finance, insight and Markets
264+4%0%0$65.2MDebt$3.9M, Aug 2026
34
AI tax filing for complex returns
40+3%+11%0$15.8MSeries A$13M, Apr 2021
35
We use solar and wind power to make zero net carbon electrofuels
43+2%+5%0$150KSeries B$150K, Sep 2021
36
The all-in-one HR and payroll platform for global teams
9,642+1%+21%144$1.3BSeries E$300M, Oct 2025
37
Online engineering college for India. Learn technical skills & get…
1,192+1%+2%1$17.6MSeries A$17.5M, Aug 2021
38
Southeast Asia’s e-commerce logistics and enablement platform
9810%+2%0$132MSeries C$43.7M, Apr 2022

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 W19 companies

How many YC W19 companies are there?

194 companies were in Y Combinator's Winter 2019 batch (W19); 117 are active.

Which YC W19 companies are hiring?

19 companies posted roles in the last 60 days, led by Deel (144 roles), Alpaca (46 roles) and Overview (24 roles). 33 mark themselves as hiring on YC's directory.

Which YC W19 companies are growing fastest?

By team growth over 6 months (10+ people): Axel Travel (+71%), OutRival, Inc. (+45%) and Ashby (+31%).

Which YC W19 companies raised the most?

Largest latest rounds in the last 12 months, after their YC batch: Kalshi ($30M), Inito ($29M) and Handle ($27M).

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