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Free Email Validation API. Open Source Platform For APIs. & $25M ARR AI Tool
Chris Bulen & Eromosele Ebohon
October 13, 2025
Hey friends 👋
Good afternoon! It’s Chris & Daniel here with another edition of Startups.fyi — where we uncover the smartest tools, underrated startups, and business models worth stealing.
Whether you’re deep in build mode or just exploring your next big idea, we’ve got something for you. This week, we’re diving into a fresh batch of startups across different industries — each with unique angles, clever execution, and serious potential.
As always, we’d love to hear from you! If there’s something you’d like us to cover, just reach out to us on X and say hi 👋🏾.
It’s Monday, and for entrepreneurs with startups and side hustles, this means the start of another week of helping the world and making money!
Oh, and if you’re new here, welcome to the crew! Sign up for free to access our archive of past editions. Let’s make your entrepreneurial journey one to remember!
Today: 6 successful startups across 6 different categories.
P.S - Last week, we shared something special with you — a brand new AI-powered tool to help you discover startup ideas with real million-dollar potential. It’s our gift to you, and you can find it in today’s Roundup section! 🎁 Don’t miss it — this tool is designed to spark your next big idea.
Cursor hit $10B with 60 people. Linear serves 15,000+ customers with 80.
The future of scaling isn’t about headcount...it’s about efficiency.
Join Cristina Cordova (COO, Linear; ex-Stripe, Notion) as she unpacks how top startups are optimizing for revenue per employee, not vanity growth.
Learn how to:
💡 Build collapsible teams
💡 Identify when it’s really time to hire
💡 Keep craftsmanship alive while scaling fast
📅 Oct 15 | 11 AM PT
🎙️ Cristina Cordova, COO at Linear
🧢🎁 First 25 people to engage during the live session get a limited-edition “First Principles” dad hat.
Startups FYI Spotlight
Here is an e-com AI agent for listing products on different platforms with ready made visuals and copy that convert real buyers (Pre-revenue)
Discover this easy-to-use AI-powered executive intelligence briefings for global trade and supply chain operations (Pre-revenue)
Here is a fast, accurate email validation API that uses real SMTP checks to keep your lists clean and your deliverability high (Pre-revenue)
This AI Prompt library for developers lets you browse, create, manage, and share curated prompts optimized for tools like ChatGPT, Claude, and Gemini. This tool is already at $100 MRR as a side project for the solo founder.
Here is another easy-to-use online tool that helps you calculate future or past dates instantly. Perfect for planning projects, deadlines, or events. This tool makes $300+ MRR.
This tool is an open-source platform and framework for building, managing and federating APIs, especially GraphQL in a type-safe scalable way. This tool makes $2,000 MRR.
—Let’s get YOUR startup listed!
👉 Use this link to share your project with 14,000+ startup founders, entrepreneurs and indie makers.
Ghostwriting for Founders: Playbookz creates done-for-you LinkedIn posts, lead magnets, and campaigns. Clients drove 2M+ reach and 1,000+ MQLs last year. Get 20K+ views in 28 days or you don’t pay.
Startups FYI Roundup
→ The Startups.fyi Tool That Finds $1M Startup Ideas
We've created something special just for our Startups.fyi community! Our exclusive tool scans internet forums, niche communities, and trending discussions to surface high-potential business ideas that are flying under the radar.
it ranks and filters hundreds of concepts, showcasing the most promising ones based on real market signals. 👉 Try the tool here →
→ How Levelset scaled to $25M ARR, then sold for $500M
Levelset helped contractors get paid faster by automating lien rights. Through smart upsells and refined sales motions, they hit $25M ARR before Procore acquired them for $500M. 👉 Read the full story →
→ How Jenny AI turned failure into a $25M SaaS
After multiple failed startups, the founders built Jenny AI, an AI writing assistant that went viral through smart content marketing and word of mouth. Within a short time, it hit $25M in revenue with no major funding. 👉 Read the full story →
(Tag @ChrisBulen to get your project featured in next week’s roundup)
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That’s it for this time! See you again next week.
— Chris (@ChrisBulen)