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YC S15 companies (Summer 2015)

All 104 companies in Y Combinator's Summer 2015 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
36 roles
Human InterestS15
  1. 2Eight Sleep16
  2. 3Fountain14
See all 16
Fastest growingteam, 6 months
+32%
80,000 HoursS15
  1. 2Eight Sleep+17%
  2. 3Human Interest+12%
See all 18
Shrinkingteam, 12 months
−43%
SnapMagicS15
  1. 2Verge Genomics−21%
  2. 3Zeplin−21%
See all 11
Raised the mostlast 12 months
$50M
Eight SleepS15
  1. 2TetraScience$15M
  2. 3Cofactor Genomics$1.2M
See all 3
Companies
104
Active
44
Hiring, last 60 days
16
Open roles, 60 days
128
People on these teams
11,491
Showing 50 of 104 companies
CompanyTeam6 mo12 moOpen rolesTotal raisedLast round
A flexible work app that connects businesses with hourly workers.
2,747+7%+16%2$148MSeries D$60M, May 2023
The 401(k) for small and medium-sized businesses.
930+12%+20%36$915MUndisclosed round$100M, Oct 2025
AI-powered contract management
868+3%+15%1$334MSeries E$150M, Jan 2022
Provides payment infrastructure for Southeast Asia
6270%−2%14$535MSeries D$300M, May 2022
Bluecrew is a web based staffing agency.
620+4%+10%0$3.2MUndisclosed round$2.5M, Jan 2017
A learning platform that enables you to train your staff or customers.
581−4%−10%YC$402MUndisclosed round$30M, May 2023
Digital trade finance and B2B commerce company
444+5%+16%YC$578MDebt$50M, Oct 2025
High volume hiring made simple
425+2%+5%14$219MSeries C$100M, Jun 2022
PartnerStack is a full stack solution for partnerships.
374+5%+7%0$36.2MSeries B$28.9M, May 2021
3690%+4%0
Modern primary care via video and in-person
337 −4%4$12.5MEquity crowdfunding$3.5M, Mar 2019
The Infrastructure Identity Company
329+12%+31%6$169MSeries C$110M, May 2022
The sleep fitness company.
282+17%+26%16$302MSeries D$50M, Mar 2026
Scentbird is a luxury fragrance subscription service.
242+4%+10%2$29.6MUndisclosed round$820K, Nov 2023
The only R&D data cloud for life sciences
227+6%+32%13$114MUndisclosed round$15M, Feb 2026
Powers OTT online video providers with video developer tools.
180+8%+10%2$95.3MDebt$3M, Oct 2024
Move anything, anytime, anywhere
179+8%+13%1$3.9MSeed$3.8M, Jun 2017
The fundraising platform for schools.
148+9%+18%9$50MPrivate equity$50M, Sep 2022
Oolu is one of the fastest growing off-grid solar firms in West Africa
138−1%−2%0$14.7MDebt$300K, Sep 2022
An online guide that tells talented graduates how to maximise the…
121+32%+78%0$120KYC investment$120K, Aug 2015
We pioneer solutions to end the global housing crisis by empowering…
119 −1%YCGrantAug 2015
Build and manage distributed teams
89−1%−6%0$32.6MSeries B$20M, Aug 2017
Credit cards for Indians that banks cannot see
880%0%0$6.6MUndisclosed round$3.9M, Mar 2019
Career advancement for Black, Latinx & Native American professionals.
83+12%+15%0$11.9MSeries A$7.5M, Sep 2017
Deliver on the Promise of Design
61 −21%0$1.4MSeed$1.2M, Jul 2016
Workforce Management for Large Farms
490%+4%0Series BJan 2022
Tesorio is the cash flow performance platform that helps finance…
44+5%−2%0$33.9MSeries B$17M, Jul 2022
Become the leader your company needs.
41−9%+5%0
Branch8 helps sellers to list and manage products on e-commerce…
40 −2%YCNon-equity supportJan 2019
Long range, wireless energy distribution that scales
39+3%−5%YC$39.1MGrant$30M, Jun 2026
Scope AR is the leading provider of User Guided Augmented Reality…
38−12%−16%0$11.8MUndisclosed round$9.7M, Dec 2022
HER helps lesbian, bisexual and queer people meet each other
37 −5%0$2MYC investment$120K, Aug 2015
Revenue generation for live events
370%−5%0$3.1MSeed$2.5M, Jun 2019
Rare Disease-Focused Care Delivery and Evidence Generation Platform
31 +7%0$120KYC investment$120K, Aug 2015
Gemnote is the easiest way to design, create and send custom products.
28+4%+22%YC$120KYC investment$120K, Aug 2015
Hickory turns your employees into experts.
260%−4%0$3.3MSeries A$3.2M, Jan 2017
We use human data and AI to develop better drugs faster.
26−4%−21%2$134MSeries C$98M, Oct 2024
Xfers makes it possible for people to make and receive payments via…
26−4%−7%0$32.6MCorporate round$30M, Mar 2021
Values based personalization at scale for asset and wealth management
25−7%−31%0$24.3MSeries A$10.5M, Apr 2020
Social Infrastructure for Games; Makers of Nakama game server, Satori…
240%0%0$120KYC investment$120K, Aug 2015
Worlds smallest and friendliest café franchise. "The Bike-Powered…
22−4% 0$3.4MUndisclosed round$944K, Jul 2017
AI-assisted electronics design
20−20%−43%5
We help residential property managers eliminate vacancy.
20−17%−13%0$620KSeed$120K, Mar 2016
Reliable and affordable solar energy in developing countries.
17+6%+6%0$120KYC investment$120K, Aug 2015
Icons and social logos for your website.
170%0%0$701KEquity crowdfunding$701K, Nov 2016
Predicting and preventing heart disease.
15−6%−12%0$15.8MSeries A$11.2M, Aug 2020
Autonomous shuttles for campus-like environments.
150%0%0$2.2MSeed$2.1M, Apr 2016
We design and manufacture energy efficient LED lighting fixtures for…
13 +8%0$3.1MUndisclosed round$2M, Apr 2018
Cofactor closes the precision medicine gap with predictive diagnostics
130%+18%0$28.9MUndisclosed round$1.2M, Dec 2025
Laboratory Information Management System (LIMS) serving…
120%0%0$20.4MConvertible note$1.8M, Apr 2021

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 S15 companies

How many YC S15 companies are there?

104 companies were in Y Combinator's Summer 2015 batch (S15); 44 are active.

Which YC S15 companies are hiring?

16 companies posted roles in the last 60 days, led by Human Interest (36 roles), Eight Sleep (16 roles) and Fountain (14 roles). 18 mark themselves as hiring on YC's directory.

Which YC S15 companies are growing fastest?

By team growth over 6 months (10+ people): 80,000 Hours (+32%), Eight Sleep (+17%) and Human Interest (+12%).

Which YC S15 companies raised the most?

Largest latest rounds in the last 12 months, after their YC batch: Eight Sleep ($50M), TetraScience ($15M) and Cofactor Genomics ($1.2M).

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