Chrome Extensions development at ZeroPixel
A browser extension puts your product inside the tool your users never close. It can read and act on the page they're viewing, automate what they do repeatedly, and surface your service at the exact moment it's useful — capabilities no website or app can replicate. It's also a genuinely different engineering discipline, which is why so few agencies do it well.
ZeroPixel builds extensions as products, not scripts. We ship our own — AutoFyl, an AI-powered form filler used in the wild — so we know the whole lifecycle first-hand: Manifest V3's service-worker model, content scripts that survive hostile pages, cross-browser quirks, Chrome Web Store review, and the update discipline that keeps thousands of installs working.
The work splits roughly in two. Companies commission internal extensions — tools that automate their team's daily browser work, often paying for themselves in weeks. And founders commission product extensions — standalone tools or browser companions to an existing SaaS. We build both, in TypeScript and React, to the same standard as everything else we ship.
Extensions we build
Four shapes cover most extension work — what they share is living usefully inside the page your user is already on.
Productivity & automation tools
Extensions that fill, extract, annotate and automate — turning your team's repetitive browser work into a keyboard shortcut.
SaaS companion extensions
Your product, present wherever users browse — clip to your app, act on any page, stay signed in alongside your main product.
Research & data tools
Structured capture from the pages your team reads all day — into your CRM, spreadsheet or database, correctly, every time.
AI-powered extensions
LLM features in the browser — summarise, draft, and act on page content — engineered so keys stay secret and costs stay controlled.
Why hire ZeroPixel for extension work
- We ship our own
- AutoFyl is ours end to end — build, store review, updates, users. Agencies that have only built client demos haven't met the problems that appear after ten thousand installs. We have.
- Manifest V3 from the start
- Chrome's current extension platform has strict rules on background work and permissions. We build natively to it — no legacy patterns that will need an emergency rewrite at the next deprecation.
- Store review, handled
- Chrome Web Store review rejects extensions for unclear permissions, privacy gaps and sloppy listings. We've been through it; minimal-permission architecture and a compliant listing are part of the build, not an afterthought.
Chrome Extensions — common questions
What can a Chrome extension actually do?
Anything that involves reading or acting on web pages your users visit: filling forms, extracting data, adding buttons and panels to sites you don't control, automating multi-step tasks, checking content against your systems. The practical question is whether your users' work happens in a browser — if it does, an extension can usually remove a chunk of it.
Will it work in Edge and Firefox too?
Yes — Edge runs Chrome extensions almost unchanged, and we build with a compatibility layer that targets Firefox from the same codebase. One build, reviewed and published across the stores your users actually use. Safari is more involved; we'll scope it honestly if your audience needs it.
How much does a Chrome extension cost to build?
Internal tools with focused scope are typically low-to-mid four figures; consumer-grade product extensions with accounts, sync and store polish sit higher — always a fixed written quote. Extensions are often cheaper than the web apps they replace, because the browser provides the UI context you'd otherwise have to build.
Can you handle the Chrome Web Store listing and review?
Yes, end to end: privacy policy, permission justifications, store assets and the listing itself, plus fixes if reviewers push back. Post-launch we handle updates too — Chrome's platform changes regularly, and installed users expect the extension to just keep working.
Extension or web app — how do we choose?
One question decides most cases: does the tool need to act on other websites, or at the moment users are elsewhere? If yes, that's an extension — a web app can't reach into other pages. If your tool is a destination users visit deliberately, a web app is simpler and needs no store approval. Plenty of products end up as both, sharing one backend; we build that too.
Beyond Chrome Extensions
A stack is a set of choices that have to work together — these are the pieces we most often pair with Chrome Extensions, and where we do it.
Building with Chrome Extensions?
Tell us what you're making — we'll reply within one working day with an honest take and a fixed quote.