Website agency for Y Combinator companies

Your Website: The First and Last Chance to Impress

Your website is often the first—and sometimes only—chance to convince visitors that your startup is worth their time. But here's the issue: many startup websites are cluttered, confusing, or miss what customers truly care about.

I've spent hours watching Y Combinator partners critique startup websites. These are the experts who evaluate thousands of startups each year, and they know exactly what makes some websites convert and others leave potential customers wondering what went wrong.

Let’s break down the key principles for building a website that turns visitors into customers. No fluff, just actionable advice.

1. Show, Don’t Tell: Developer Tools

Technical founders love to talk about their tech, but developers don’t want to read about it—they want to see it. Here’s how to get it right:

• Show the product upfront: Don’t bury your tool under a block of text. Let visitors see it in action immediately. Think interactive demos or real-time usage examples.
• Build trust with credibility: Developers value GitHub stats, community support, and solid documentation. Focus on showcasing technical credibility rather than flashy animations.
• Be clear about your target audience: “A platform for developers” is vague. Specify which developers your tool is for and what problems it solves.

2. Design That Converts: It’s More Than Just Looks

Good design isn’t just about aesthetics—it’s about driving user behavior.

• CTA placement matters: Place your action buttons where users make decisions. Don’t bury them in the navigation.
• Visual hierarchy is key: Use size and color to guide the user’s eyes toward important elements.
• Don’t overwhelm visitors with options: Simplicity is powerful. Reduce choices at each stage of your site to keep users focused.

3. Mobile Optimization: A Must for Conversion

Don’t underestimate the power of a seamless mobile experience. If it’s difficult to navigate on mobile, your conversions will drop.

4. Stripe’s Approach: Simple Yet Powerful

Stripe’s website is a masterclass in balancing complexity and simplicity. Here’s what you can learn:

• Documentation as marketing: Make your documentation a powerful entry point. Well-designed, useful docs can actually be a high-converting tool.
• Progressive disclosure: Show users only what they need at each stage. Avoid overwhelming them with too much information.
• Typography hierarchy: Use font sizes and weights strategically to create a clear reading flow.

5. AI Startups: The AI Buzzword Trap

In the AI space, overusing vague terms like “AI-powered” makes you sound just like everyone else. Instead:

• Show the AI in action: Give visitors interactive demos so they can see the technology at work.
• Start with problems, not technology: Lead with the specific issues your AI solves, then introduce your AI as the solution.

6. Webflow’s CEO on Design and Performance

Webflow’s CEO shared an essential truth: performance is just as important as design. Slow-loading sites lose customers. Prioritize speed and technical optimization to keep users engaged.

7. Putting It All Together: Your Conversion Checklist

Now, how do you measure your website’s performance? Use this checklist:

• 5-second test: Can visitors quickly understand what your company does, who it’s for, and what action they should take? If not, your messaging needs work.
• Conversion path audit: Examine every step in your user journey. Is every click and field necessary? Streamline where possible.
• Mobile conversion test: Is your site optimized for mobile? Test it on real devices and fix any friction points.
• Technical performance: Run your site through tools like Google PageSpeed and GTmetrix to measure and improve loading speeds.
• Social proof: Ensure your testimonials and case studies are specific, relevant, and speak to your target audience’s pain points.

The Bottom Line: Build for Conversion, Not Design Awards

The most successful websites aren’t the most beautiful—they’re the ones that understand their users, minimize friction, and guide visitors toward conversion with clarity.

Your website isn’t an art project. It’s a conversion machine. Build it with that in mind, and you’ll see real growth.