A few months ago I decided to build and publish 10 Chrome extensions as a portfolio project. Not because I expected to get rich from them, but because I wanted to understand the Chrome Web Store ecosystem, manifest V3, and what it actually takes to ship browser extensions.
Here's what I built, what I learned, and the two extensions I'm most proud of.
The Extensions
| Extension | What It Does | Status |
|---|---|---|
| SEO Inspector | Analyze any page's SEO signals | Published |
| JSON Formatter Pro | Pretty-print JSON in the browser | Published |
| Quick Currency Converter | Real-time currency conversion popup | Published |
| Domain WHOIS Lookup | WHOIS data on any domain, instantly | Published |
| AI Text Rewriter | Rewrite selected text with AI (BYOK) | Published |
| Color Picker & Converter | Pick colors from any webpage | Published |
| Page Speed Checker | Google PSI scores without leaving the tab | Published |
| Hash & Encode Tool | MD5/SHA/Base64 encode/decode | Published |
| Lorem Ipsum Generator | Insert placeholder text anywhere | Published |
| Regex Tester | Test and debug regular expressions | Published |
All built with Manifest V3, Apple-inspired dark UI, no backend required.
The Two I'm Actually Using Daily
AI Text Rewriter
This one uses your own OpenAI API key (BYOK — Bring Your Own Key) to rewrite any selected text on a webpage. Select text, right-click, choose a rewrite style (professional, casual, concise, expand), and you get a rewritten version instantly.
The BYOK model is important: no subscription, no rate limits on my end, your API key stays in your browser's local storage.
Domain WHOIS Lookup
Dead simple: click the extension icon while on any domain, get full WHOIS data including registration date, expiry, registrar, nameservers. Useful for competitive research, checking if a domain is about to expire, or verifying ownership.
Uses my own WHOIS API on RapidAPI under the hood — so it's fast and reliable.
What I Learned About the Chrome Web Store
The good:
- Extensions genuinely useful enough to use daily are easy to build
- Manifest V3 migration isn't as painful as people say
- The store fee ($5 one-time) is absurdly cheap
The hard parts:
- Review times are unpredictable (3 days to 3 weeks)
- Rejection reasons can be vague ("insufficient functionality" with no further detail)
- Permissions are scrutinized — request only what you actually need
- Some extensions got rejected and required multiple resubmissions
The surprising part:
The Chrome Web Store has significant organic discovery. Even without marketing, extensions get installs just from people searching for specific functionality.
The Technical Approach
All 10 extensions share:
- Manifest V3 (required now)
- Service workers instead of background pages
- Minimal permissions (principle of least privilege)
- No external analytics or tracking
Structure for each:
extension-name/
├── manifest.json
├── popup.html
├── popup.js
├── background.js (service worker)
├── content.js (if needed)
└── icons/
├── 16.png
├── 48.png
└── 128.png
Revenue Reality
Current revenue: $0 (all free).
The monetization plan is freemium: lock advanced features behind a one-time payment via Gumroad or Stripe. That's phase 2 — first I needed to validate that people actually use these.
Early signals are positive: installs are accumulating organically without any marketing.
What's Next
- Freemium gating on the most-used extensions
- Tab Manager & Session Saver (currently in review — 3 session limit on free plan)
- More AI-powered extensions as the BYOK model proves out
If you're considering building Chrome extensions, the barrier is lower than you think. Start with something you personally want to use. That's the best filter.
Questions about Manifest V3, the review process, or any specific extension? Happy to dig in.
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