Every resource founders actually use, in one library.

What founders use most, ranked by how many answers lean on it.

1. Clay is the tool most outbound teams reach for when they want research-driven personalization instead of name placeholders. It... Clay Tool · Starting Up Clay Clay Labs, Inc.
2. When you have a name and a company but no address, Hunter is the default first stop: type the person and the domain, and it... hunter.io Tool · Starting Up Hunter Email Finder Hunter
3. Video · Starting Up Y Combinator's Brutally Simple Playbook to Get Your First 100 Customers Y Combinator
4. Batko is a two-time founder and former Startmate CEO who has received thousands of cold emails, so he writes from the receiving... batko.ai Article · 15 min read · Starting Up Cold Email Templates for Founders: 5 Templates That Get Replies Michael Batko
5. Sometimes your emails are not ignored, they never reach the inbox, and no amount of copy editing fixes a deliverability... instantly.ai Tool · Web app · Starting Up Instantly Cold Email Outreach and Deliverability Instantly
6. This is the piece that separates organic word of mouth from an engineered viral loop, and shows you how to actually design one.... andrewchen.com Essay · Long essay, about 15 minute read · Starting Up What's Your Viral Loop? Understanding the Engine of Adoption Andrew Chen
7. If you decide to run WhatsApp at any real scale, you cannot do it from the plain WhatsApp Business app: you need a... AiSensy Tool · Free plan, paid tiers from about 1,395 rupees per month · Starting Up AiSensy: WhatsApp Business API Platform AiSensy Communications Private Limited
8. This is the cleanest side-by-side we found on what you actually trade away going indirect: margin, customer contact, and... GTM Playbook Article · Long-form article, about a 12 minute read · Starting Up Direct Sales vs. Channel Sales: Choosing Your Route to Market in B2B SaaS James Doman-Pipe
9. Video · Talk, roughly 30 to 45 minutes · Starting Up Partner Ecosystems: Trends, Predictions and Forecast, with Jay McBain Jay McBain
10. If you are asking whether SEO is still worth it, start by learning what good SEO in 2026 actually looks like, and this free... Ahrefs (YouTube) Course · ~2 hours across a short video series · Starting Up SEO Course for Beginners (by Ahrefs) Sam Oh (Ahrefs)
11. SEO feeling slow usually means you are doing it one blog post at a time, and this essay covers the scalable side: generating... Knownful Essay · ~15 minute read · Starting Up What is Programmatic SEO and should your startup use it? Matthis Duarte
12. Video · Starting Up How to Test Facebook Ads Creatives at Every Budget Dara Denney
13. This lays out the case that your product can be its own distribution, so you sell less by design. It is aimed at exactly the... Bessemer Venture Partners Essay · About a 20 minute read · Starting Up 10 Product-Led Growth Principles Janelle Teng and Ethan Kurzweil (Bessemer Venture Partners)
14. Before you sink 50 to 120 hours into a launch, read this honest first-person account of what a launch actually returned across... Plain Sight Ventures Essay · Short essay, roughly a 6 minute read · Starting Up Is Product Hunt Worth It? Jason Walkow
15. This is the clearest essay on why a flattening cohort retention curve is the thing that actually matters, and it lives on... andrewchen.com Essay · ~12 min read · Starting Up Retention is King Jamie Quint
16. Benchmarks are useless until you can actually plot your own cohort curve, and Mixpanel's free tier lets you build a real... Mixpanel Docs Tool · Docs guide, ~15 min to set up · Starting Up Track user retention with Mixpanel Mixpanel
17. PostHog is one all-in-one product analytics platform (events, funnels, session replay, feature flags) instead of a pile of... PostHog Docs Tool · Starting Up Self-host PostHog PostHog
18. Most first-time founders either track nothing or drown themselves by logging every click, and this piece makes the case for the... Mean CEO Essay · Starting Up Event Tracking Strategy: What to Measure and Why Violetta Bonenkamp
19. This is the piece that answers the second half of your question head on: when is it too early to even care. Skok's site is the... For Entrepreneurs (David Skok) Essay · Starting Up Why Early-Stage Startups Should Wait to Calculate LTV:CAC, and How They Should Use It When They Do Jared Sleeper and David Skok
20. US benchmarks quietly assume US ACVs and US venture cash, so they mislead an Indian founder. This piece grounds the numbers in... upGrowth Article · Starting Up CAC Benchmarks for Indian B2B SaaS by ARR Band: The Real Numbers for 2026 Amol Ghemud
21. A founder-voice conversation, not a metrics lecture, on why a pretty LTV:CAC ratio can still sink you if the cash takes years... The SaaS Podcast (SaaS Club) Podcast · Starting Up How to Calculate CAC, LTV, Retention and Churn (Startups Unplugged with Paul Orlando) Omer Khan (host), Paul Orlando (guest)
22. Video · About 35 minutes · Starting Up Building a Growth Machine (Relay Ventures CEO Summit 2018) Brian Balfour
23. This gives you the mental picture and the evidence in one place: a bucket full of holes barely fills no matter how fast you... Amplitude Article · Starting Up The Leaky Bucket Problem: More Users Don't Mean More Long-Term Growth Noorisingh Saini
24. Most active-user counts quietly measure app opens, which is exactly the dishonesty this question is trying to avoid. This piece... Mixpanel blog Article · Starting Up Monthly active users (MAU): Definition, formula, and 2026 benchmarks Mixpanel

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