In this episode of Startup School, YC Group Partner Tom Blomfield discusses one of the most important elements of running any startup: metrics! Tom shares what key metrics to track and how to use them to make the best decisions for your company. Apply to Y Combinator: https://yc.link/SUS-apply Work at a startup: https://yc.link/SUS-jobs Chapters (Powered by https://bit.ly/chapterme-yc) - 00:00 - Intro 00:21 - Importance of Metrics 01:16 - Pre-launch Metrics 02:23 - Metric Overload Caution 03:17 - Key Metrics Selection 04:54 - Consistency in Metrics 07:13 - Investor Update Metrics 09:17 - Retention's Significance 13:13 - B2B SaaS: Net Dollar Retention 16:50 - Cruciality of Gross Margin 21:10 - Challenges of Negative Margin Scaling 22:18 - Metrics Recap 22:42 - Final Thoughts 23:24 - Outro
In this episode of Startup School, YC Group Partner Tom Blomfield dives deeper into the metrics that matter most for consumer startups. Tom discusses paid and organic user growth, unit economics, net promoter scores, and the "magic moment" in your product that is most important to track. Apply to Y Combinator: https://yc.link/SUS-apply Work at a startup: https://yc.link/SUS-jobs Chapters (Powered by https://bit.ly/chapterme-yc) - 00:00 - Intro 01:00 - Growth Rates 01:24 - Organic vs. Paid Growth 05:27 - Cannibalization 06:21 - Paid Growth 10:59 - Unit Economics 17:04 - Net Promoter Score (NPS) 20:23 - Recap 22:14 - Outro
AI coding agents are no longer a distant idea—they're already starting to reshape how we work. YC's Tom Blomfield and David Lieb discuss how AI coding tools are transforming software development, why small, high-agency teams will be able to do what once took armies of engineers, and why there's never been a better time to start something new. They explore the bigger picture too: a future where there's more abundance, knowledge work becomes more accessible, and founders have more leverage than ever before. If you're thinking about building, there's no better moment than right now. Apply to Y Combinator: https://ycombinator.com/apply Work at a startup: https://workatastartup.com Chapters (Powered by https://chapterme.co/) - 0:00 Intro 0:46 The combine harvester argument for AI 2:23 Building with no-code tools 5:37 The arguments against AI coding 7:01 Jevons Paradox 9:26 What happens to the software jobs of today? 12:16 How will these tools affect knowledge work? 15:08 The transitory challenge period for people 16:21 Advice for future founders
In this recent batch talk, YC General Partner Tom Blomfield breaks down how to build a self-improving company using AI. He'll cover how to create a series of recursive, self-improving AI loops and explain why the founders who get this right will run companies that can improve while they sleep. Chapters: 00:00 — Companies Are Roman Legions 00:54 — Copilots Are the Wrong Mental Model 01:55 — Extract the Domain Knowledge 02:24 — The Recursive Self-Improving Loop 04:12 — The Holy Shit Moment at YC 05:50 — Self-Optimizing Product and Support Loops 06:29 — Burn Tokens, Not Headcount 07:23 — Middle Management Is Over 08:05 — Make Everything Legible to AI 09:40 — Regenerating the YC User Manual 11:19 — Software Is Ephemeral, Context Is Valuable 12:18 — Where Humans Still Matter Apply to Y Combinator: https://www.ycombinator.com/apply Work at a startup: https://www.ycombinator.com/jobs
AI can't yet one-shot an entire product—but with the rise of vibe coding, it's getting close. YC's Tom Blomfield has spent the last month building side projects with tools like Claude Code, Windsurf, and Aqua, seeing just how far you can push modern LLMs. From writing full-stack apps to debugging with a single paste of an error message, AI is becoming a legit collaborator in the dev process. This video is a playbook for anyone who wants to get the most out of vibe coding and build faster. Apply to Y Combinator: https://ycombinator.com/apply Work at a startup: https://workatastartup.com Chapters (Powered by https://chapterme.co/) - 0:00 Intro 0:54 Some vibe coding tips from YC X25 founders 4:12 First, pick your tools and make a plan 6:27 Use version control 7:23 Write tests 8:14 Remember, LLM's aren't just for coding 8:57 Bug fixes 11:10 Documentation 12:03 Functionality 13:20 Choose the correct stack 15:08 Refactor frequently 15:40 Keep experimenting! 16:21 Outro
If you're a startup founder, how much should you charge for your product or service? It's a simple question that can make many lock up. What number should you pick? In this episode of Startup School, YC Group Partner Tom Blomfield guides you on how to come up with a price and then justify that number to customers. Apply to Y Combinator: https://yc.link/SUS-apply Work at a startup: https://yc.link/SUS-jobs Chapters (Powered by https://bit.ly/chapterme-yc) - 00:00 - Intro 01:19 - The Value Equation 04:28 - Cost 06:26 - Competition 10:08 - Pricing 13:42 - Free trials 16:42 - Recap 17:30 - Outro
This weeks episode entitled 'Monzo CEO On Death Threats, Depression & Digital Banking Wars: Tom Blomfield' topics: 0:00 Intro 02:52 Why entrepreneurship? 06:04 What made you want to disrupt an industry? 16:32 Monzo & Starling rivalry 21:23 Starting Monzo 27:13 Wanting to be seen to be a success 33:59 What were the good times at Monzo? 39:07 What were the bad times at Mozo? 46:22 Was the business model of Monzo bad? 54:35 Leaving Monzo 59:08 Not sleeping because of the stress of the business 01:04:14 How was holding down a relationship while running the business? 01:07:47 The “red phone” in your bedroom 01:12:11 What was your life like outside of the business? 01:13:06 The road to leaving Monzo 01:20:29 The urge to go back 01:26:57 Death Threats 01:32:42 Enjoying the small things in life and relationships 01:35:34 Your purpose in life 01:36:49 Crypto currencies 01:39:51 The good things about being a CEO Tom: https://twitter.com/t_blom https://www.linkedin.com/in/tomblomfield Listen on: Apple podcast - https://podcasts.apple.com/gb/podcast/the-diary-of-a-ceo-by-steven-bartlett/id1291423644 Spotify - https://open.spotify.com/show/7iQXmUT7XGuZSzAMjoNWlX FOLLOW ► Instagram: https://www.instagram.com/steven/ Twitter: https://twitter.com/SteveBartlettSC Linkedin: https://www.linkedin.com/in/steven-bartlett-56986834/ Sponsors: https://uk.huel.com/ https://fiverr.com/ceo
You might think that pivoting is something done only by the startups that don’t make it. In reality, a huge number of the best startups pivoted. In this first episode of our new series, Office Hours, Y Combinator Group Partners share their favorite stories of entrepreneurs who pivoted and went on to build game-changing companies. The group of startup experts also share their own pivot stories and help answer the questions: How do you know if it’s time for your startup to pivot—and how will you know if that next idea is the one? Apply to Y Combinator: https://yc.link/OfficeHours-apply Work at a startup: https://yc.link/OfficeHours-jobs Chapters (Powered by https://bit.ly/chapterme-yc) - 00:00 - Intro: How To Pivot 00:37 - Favorite Pivots 00:53 - Brex 02:40 - Goat 04:55 - Tom Blomfield: Billion Dollar Startup 07:52 - Clipboard Health 08:49 - The Secret to Finding the Right Problem 10:28 - Pivot Hell 13:43 - Diana Hu's Startup 16:23 - Picking The Right Metrics To Follow 16:47 - Favorite Understanding Of Pivoting 18:34 - Find And Track Your Main KPI 20:02 - Outro: Pivoting Process
Navigating B2B sales for the first time can feel slow and overwhelming. Drawing from his experience founding Monzo and GoCardless, YC's Tom Blomfield shares his playbook for running a tight sales process that lands real, recurring revenue. He walks through each step—free and paid pilots, opt-out contracts, long-term deals—and shows how to prove value and close customers. Apply to Y Combinator: https://www.ycombinator.com/apply Work at a startup: https://www.ycombinator.com/jobs Chapters: 00:21 - The Typical B2B Sales Progression 01:00 - Common Pitfalls in Early Stages 01:38 - Understanding Design Partnerships 02:56 - Identifying Customer Problems 04:18 - Avoiding Overbuilding 06:11 - Transitioning to Free Trials 07:11 - Defining Success Metrics 08:38 - Overcoming Customer Objections 10:01 - Moving to Paid Trials 10:20 - Securing Financial Commitments 11:30 - Optimizing Pilot Engagement 13:47 - Recurring Revenue Contracts 15:33 - Focusing on Customer Success
There aren’t a ton of people in the world who can say they founded a billion dollar company. There are far fewer that can say they did it twice. YC Group Partner Tom Blomfield is one of them. Each episode of our series Backstory will introduce you to one of YC’s Group Partners and the path they took to get here. If you aspire to change the world with your startup, Tom's story exemplifies the joys and trials of pursuing these ambitious ideas. Apply to Y Combinator: https://yc.link/Backstory-apply Work at a Startup: https://yc.link/Backstory-jobs Chapters (Powered by https://bit.ly/chapterme-yc) - 00:00 - Intro 02:52 - GoCardless 05:07 - Starting Monzo 08:46 - COVID challenges 10:24 - Stepping away from Monzo 13:10 - Joining Y Combinator 13:54 - Outro Directors: Ryan Loughlin Zach Both Director of Photography: Matt Piniol Editors: Hoku Uchiyama Zach Both Ryan Loughlin Additional footage provided @jakewrightnet