Source-status visible
YC companies
6016
Filtered out of 6018 total.
Tracked monthly visits
19.1B
Visits of active search subset.
Cohort years
2005-2026
Old-to-new timeline ready.
TrafficLens verified
4299
QA blocks fake live claims.
Year
Category
Status

Attention Ranking

Proprietary compound score mapping traffic quantity, quality, commercial intent, loyalty, and velocity.

yc-oss-refresh: YC OSS API mirror of YC Startup Directory
#1
Kalshi
kalshi.com · Winter 2019 · Fintech
Attention Ranking
81/100
Visits
17.4M
Growth
+49.1%
Email
1.1%
Direct
56.6%
#2
Vetcove
vetcove.com · Summer 2016 · B2B
Attention Ranking
80/100
Visits
1.41M
Growth
+55.9%
Email
1.9%
Direct
88.0%
#3
Prolific
prolific.com · Summer 2019 · B2B
Attention Ranking
80/100
Visits
21.1M
Growth
+28.5%
Email
4.4%
Direct
73.4%
#4
Supabase
supabase.com · Summer 2020 · B2B
Attention Ranking
80/100
Visits
28.5M
Growth
+8.9%
Email
2.1%
Direct
76.4%
#5
1000Memories
ancestry.com · Summer 2010 · Consumer
Attention Ranking
79/100
Visits
35.3M
Growth
+7.3%
Email
9.3%
Direct
57.5%
#6
9gag
9gag.com · Summer 2012 · Consumer
Attention Ranking
79/100
Visits
61.8M
Growth
-0.4%
Email
1.3%
Direct
82.1%
#7
Vidpresso
facebook.com · Winter 2014 · B2B
Attention Ranking
79/100
Visits
11.2B
Growth
-2.2%
Email
3.2%
Direct
67.8%
#8
AfterQuery
afterquery.com · Winter 2025 · B2B
Attention Ranking
79/100
Visits
977.5K
Growth
+452.9%
Email
3.9%
Direct
62.6%
#9
Axiom
axiom.trade · Winter 2025 · Fintech
Attention Ranking
79/100
Visits
5.51M
Growth
+2.5%
Email
0.6%
Direct
73.7%
#10
Pax Historia
paxhistoria.co · Winter 2026 · Consumer
Attention Ranking
78/100
Visits
4.12M
Growth
-10.3%
Email
0.4%
Direct
61.5%
#11
Paribus
ramp.com · Summer 2015 · Fintech
Attention Ranking
77/100
Visits
5.44M
Growth
+3.7%
Email
10.6%
Direct
63.5%
#12
Replit
replit.com · Winter 2018 · B2B
Attention Ranking
77/100
Visits
12.9M
Growth
+5.7%
Email
2.0%
Direct
59.2%
#13
PostHog
posthog.com · Winter 2020 · B2B
Attention Ranking
77/100
Visits
2.87M
Growth
+27.8%
Email
2.3%
Direct
71.6%
#14
FlutterFlow
flutterflow.io · Winter 2021 · B2B
Attention Ranking
77/100
Visits
2.15M
Growth
+12.9%
Email
1.4%
Direct
57.5%
#15
StudyStream
studystream.live · Summer 2021 · Education
Attention Ranking
77/100
Visits
2.03M
Growth
+13.3%
Email
0.6%
Direct
71.3%
#16
AlgoTest
algotest.in · Summer 2022 · Fintech
Attention Ranking
77/100
Visits
1.03M
Growth
+20.1%
Email
0.3%
Direct
66.8%
#17
Airbnb
airbnb.com · Winter 2009 · Consumer
Attention Ranking
76/100
Visits
117.2M
Growth
+8.7%
Email
3.7%
Direct
45.8%
#18
NudgePad
azure.com · Summer 2009 · B2B
Attention Ranking
76/100
Visits
59.3M
Growth
-1.4%
Email
2.1%
Direct
43.7%
#19
Close
close.com · Winter 2011 · B2B
Attention Ranking
76/100
Visits
1.27M
Growth
+0.5%
Email
3.3%
Direct
79.7%
#20
Quartzy
quartzy.com · Summer 2011 · Healthcare
Attention Ranking
76/100
Visits
444.2K
Growth
+16.4%
Email
4.9%
Direct
77.3%
#21
7cups
7cups.com · Summer 2013 · Healthcare
Attention Ranking
76/100
Visits
1.76M
Growth
+14.9%
Email
1.5%
Direct
56.1%
#22
Cambly
cambly.com · Winter 2014 · Education
Attention Ranking
76/100
Visits
2.19M
Growth
+1.0%
Email
3.9%
Direct
69.0%
#23
Expo
expo.dev · Summer 2016 · B2B
Attention Ranking
76/100
Visits
5.28M
Growth
+0.9%
Email
1.1%
Direct
61.2%
#24
Faire
faire.com · Winter 2017 · B2B
Attention Ranking
76/100
Visits
8.20M
Growth
+8.4%
Email
3.7%
Direct
55.7%
#25
Acely
acely.com · Winter 2018 · Education
Attention Ranking
76/100
Visits
309.8K
Growth
+128.7%
Email
1.2%
Direct
56.8%

Traffic Distribution

direct
16.8%
search
9.2%
social
2.2%
mail
1.1%
referrals
3.0%
Loyalty = direct traffic share. Email leaderboard = mail traffic share and mail visits. Attention = duration x total visits.

Social Breakouts

Winter 2014Vidpresso
Summer 2005Reddit
Winter 2022RecordBook
Winter 2018Substack
Summer 2006Scribd
The next enrichment pass stores 12-month history and 24-hour deltas once enough daily observations exist.
Debate-It verdict
Build the spine first
The wedge is not a pretty leaderboard. The moat is the YC company graph plus recurring traffic, email onboarding capture, and startup-specific agents that convert observations into reusable execution.
Office-Hours QA gate
Trust in four seconds
Every public number carries a source status. TrafficLens rows graduate from baseline to trafficlens only after live enrichment and autoresearch contract checks pass.
Categorization
Industry, founders, revenue
Filters support industry, sub-category, batch year, founding team, revenue state, active status, and location.
Agent factory
One startup, one agent
Each profile can graduate into a public support agent trained on its site, docs, onboarding emails, and competitive position.