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Fastest growing S20 companies

The 56 YC S20 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 56 of 56 companies on this list
#CompanyTeam6 mo12 moOpen rolesTotal raisedLast round
1
Build in a weekend. Scale to millions.
484+38%+106%0$1.2BSeries F$150M, Oct 2026
2
Glimpse is the system of action for CPG retail operations
70+37%+75%3$53.4MSeries A$35M, Mar 2026
3
AI-native Robotics
27+29%+35%YCCorporate roundAug 2026
4
Take control of your data in real-time.
91+28%+102%1$6.8MSeed$6.8M, Dec 2023
5
Luminai is the AI platform for Health System Operations.
69+25%+50%4$57.8MSeries B$38M, Apr 2026
6
The spot market for semiconductors
15+25%+36%0$3.8MSeed$3M, Dec 2025
7
The first test designed to prevent birth control side effects
10+25%+43%YC$2.6MSeed$2.5M, Apr 2021
8
Vertical AI for Audit & Advisory Firms
257+24%+58%6$125MSeries C$75M, Feb 2026
9
Clinically-validated ingredients from natural microbes
32+23%+23%3$26.4MSeries A$25M, Oct 2021
10
We use AI to design antibodies for intractable diseases
28+22%+40%1$37.4MSeries A$26M, May 2024
11
Automating manual and repetitive data engineering tasks with AI
36+20%+3%4$26.2MUndisclosed round$4M, May 2025
12
Securing Nurses for Your Future
73+20%+35%YCSeedNov 2022
13
All-in-one workspace for companies making regulated products
124+19%+57%YC
14
The open source Looker alternative
33+18%+38%1$19.4MSeries A$11M, Oct 2024
15
All-in-one platform for creators to sell courses and subscriptions
122+16%+33%1$12.9MSeries A$10.8M, Nov 2021
16
🖼️ Give your software the sense of sight.
154+15%+57%7$62.2MSeries B$40M, Nov 2024
17
Ensuring AI delivers what people need, when and where they need it,…
71+15%+16%2$15.7MUndisclosed round$10.5M, Jul 2024
18
Accounting, Payments & Credit app for 60M micro-businesses in…
367+14%+31%0$80MSeries A$60M, Jun 2021
19
The tolling industry’s prime tech infrastructure
34+13%+17%4Undisclosed roundDec 2024
20
The future of B2B spend
1,421+13%+38%3$371MSeries D$190M, Oct 2024
21
Underwriting automation for small business finance
65+12%+35%1$17.8MSeries A$16.6M, Jul 2025
22
GPT Search & Merchandising for fashion e-commerce
28+12%+17%0$37MSeries A$17M, Feb 2022
23
Platform for breakthrough mental health research and treatment
78+11%+30%1$57.2MSeries B$40M, May 2022
24
Everything for your fitness or wellness business.
111+11%+18%YC$22.7MSeries A$15M, Jun 2025
25
At-Home health monitoring with silicon photonic chips for data centers
81+11%+31%1$32.8MSeries A$17M, Mar 2025
26
Transform your decision-making with reliable AI agents in weeks, not…
237+11%+22%2$209MSeries C$130M, Jun 2026
27
Modernizing global transportation payments.
187+10%+4%YC$312MSeries C$130M, Sep 2024
28
The CRM powering iconic musicians and events
33+10%+14%YC$7.5MCorporate round$3M, Oct 2022
29
India's Largest EV charging network
328+10%+13%1$46.1MUndisclosed round$18M, Feb 2026
30
Helping Plastic Surgeons Rebuild Fat
12+9%+9%0$8MSeed$2.7M, Oct 2025
31
India's leading on-demand diagnostics company
728+8%+8%1$70.8MSeries C$23.8M, Jun 2026
32
Data platform for mission-critical real-time workloads
30+7%+7%YC$14.3MNon-equity support$12M, Apr 2024
33
The all-in-one screen recorder.
15+7%+15%0$2.2MSeed$2.1M, Apr 2025
34
We make unmakeable proteins with radical advanced biomanufacturing.
47+7%+18%0$26.9MSeries A$8M, Jun 2025
35
Bits is a credit card designed to help people build credit
50+6% 1$258KYC investment$125K, Aug 2020
36
Plan, communicate, and benchmark your compensation in real-time.
304+6%+13%YC$163MSeries C$100M, Jun 2022
37
Easiest way to deploy on AWS/GCP/Azure
53+6%+23%YC$26.6MSeries A$20M, Jan 2026
38
Business-in-a-Box™ for LLCs
100+5%+10%3$11MSeries A$8M, Mar 2024
39
Kernal is creating mRNA 2.0 therapies that work in specific cells
21+5%+40%3$73MGrant$48M, Oct 2025
40
International banking infrastructure for global startups.
324+5%+13%3$653MSeries C$110M, Sep 2026
41
API that lets companies embed investment accounts into their services
49+4%+14%11$55.1MUndisclosed round$30M, Aug 2025
42
We deliver personalized medicine for neurodegenerative patients
105+4%+14%1$78.2MSeries A$25M, Nov 2024
43
Agentic AI CRM for ecommerce
353+3%+8%1$12.8MUndisclosed round$10.8M, Apr 2022
44
Absorbable wrap for blood vessels
34+3% 0$29.8MSeries A$4M, Jun 2024
45
Investment platform for MENA individuals
309+3%+11%18$37MUndisclosed round$15.7M, May 2025
46
Deliver effective learning at scale
73+3%+20%0$30.2MUndisclosed round$14.1M, Jul 2026
47
Gilgamesh Pharmaceuticals, a Clinical stage biotechnology company…
37+3%+3%0$143MSeries A$60M, Mar 2026
48
Save money and win prizes up to $10m through weekly number draws.
38+3%−5%0$26.6MUndisclosed round$10M, Feb 2022
49
Finch is the Employment Data Platform
157+3%+10%1$62.1MUndisclosed round$3.5M, Jun 2023
50
India's fastest medicine delivery in just 30 minutes
62+2%−2%0$3.1MSeed$1.6M, Jun 2025
51
The first digital payment experience company, built for B2B.
149+1%+6%1$437MDebt$350M, Nov 2022
52
Power commerce photography with generative AI
699+1%+11%3$62.1MSeries B$43M, Feb 2024
53
We train AI engineers and connect them with companies.
877+1%+2%0$11.8MSeries A$10M, May 2022
54
Home Inspections, Simplified
82+1%+4%2$22.5MUndisclosed round$5.3M, Oct 2024
55
API Platform for Banking Integrations (Plaid for India and APAC)
106+1%+5%0$8.2MSeries B$3.5M, Jun 2025
56
Zuddl is a modular platform for events and webinars that helps event…
121+1%−5%YC$15.3MSeries A$13.3M, Jan 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 S20 companies

How many YC S20 companies are there?

209 companies were in Y Combinator's Summer 2020 batch (S20); 122 are active.

Which YC S20 companies are hiring?

39 companies posted roles in the last 60 days, led by Thndr (18 roles), Atomic (11 roles) and Roboflow (7 roles). 52 mark themselves as hiring on YC's directory.

Which YC S20 companies are growing fastest?

By team growth over 6 months (10+ people): Supabase (+38%), Glimpse (+37%) and Nextera Robotics | DIDGE.ai (+29%).

Which YC S20 companies raised the most?

Largest latest rounds in the last 12 months, after their YC batch: Supabase ($150M), Taktile ($130M) and Jeeves ($110M).

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