Building a Developer Tool Portfolio: What I Learned Running 19 Utility Sites

19 single-purpose developer utility sites. Base64 decoders, IBAN generators, JSON formatters, MAC address tools. Here's what I learned.

Why Utility Sites?

1. SEO-driven traffic — people Google these tools
2. Zero support burden — no accounts, no billing
3. Compounding portfolio — 19 small sites = real business
4. Genuine utility — you're actually helping people

Key Lessons

1. Solve One Thing Perfectly

base64decode.co decodes Base64. That's it. One tool per domain. Users know exactly what they're getting.

2. Speed Is the Feature

No popups, no signups, auto-focus input, instant results. The goal: 3 seconds from Google to answer.

3. Domain Names Matter

Exact-match domains: randomiban.co, namso.io, base64decode.co. They carry SEO weight, build trust, and are memorable.

4. SEO Is Your Growth Engine

Target exact queries. Be best-in-class for that one thing. Technical SEO matters. Backlinks come through utility. Be patient — month 1 is silence, month 12 is traffic.

5. Know When to Kill

If a site isn't growing after 6 months indexed, analyze why and maybe move on.

6. The Portfolio Effect

De-risks everything. Algorithm update tanks one site? 18 others carry the load. Revenue diversified across domains.

7. Keep the Stack Boring

Same tech across all sites. Consistency is survival when you're managing 19 projects.

What I'd Do Differently

• Start content marketing earlier
• Build an email list from day one
• Automate monitoring sooner

TL;DR

Build simple tools that solve real problems. One tool per domain. Optimize for speed and SEO. Be patient. The portfolio compounds.