Full-Stack & AI Product Engineer
How much does it cost to build a Chrome extension?
A Chrome extension that does one job on the page, with no accounts and no outside services, runs $3,500 to $5,500 over about 3 to 4 weeks. Add sign-in and an outside API, or an AI feature, and it reads as $6,500 to $9,000. An extension with its own web dashboard is scoped first. These are estimates, not quotes.
Cost ranges (estimates)
- One job on the page$3,500 to $5,500About 3 to 4 weeks
Reads or changes the page, saves settings in the browser. No accounts, no outside services.
- With an API or AI$6,500 to $9,000About 4 to 5 weeks
Sign-in and one or two outside services, or one focused AI feature such as summarise or draft.
- Extension plus web appScope firstMore than one sprint
A separate dashboard, billing site, or admin console counts as a second product surface.
Prices are USD estimates, not quotes. They come from the bands in my MVP Scope Estimator and the offers on /hire. A short written scope sets the fixed price.
What these ranges assume
- One Chrome extension, one job on the page.
- Settings kept in the browser, no accounts.
- No outside services or AI in the first case.
- Standard data, nothing regulated.
- A public listing on the Chrome Web Store.
- Built by me alone, at a fixed price in writing.
What drives the cost
- A companion web app or dashboard
- Sign-in and data synced across devices
- Paid plans with billing and licence checks
- Several sites, each with its own page rules
- AI on page content, with cost limits
- Firefox, Safari, or Edge versions as well
- One site and one action on it
- Settings stored in the browser, no accounts
- Chrome only for the first version
- Free at launch, billing in a later sprint
- A short list of the exact pages to support
- An unlisted test build before the public one
How long it takes
- One job, no services: about 3 to 4 weeks.
- With sign-in and an API or AI: about 4 to 5 weeks.
- Chrome Web Store review time is set by Google.
- A written update daily, two check-ins a week.
Freelancer, agency, or no-code
I have no sourced market averages for these, so I describe fit and risks instead of quoting prices I cannot back up.
For extensions, check the Chrome Web Store policies for your use case early: permissions and data handling decide what gets approved.
Estimate your exact scope
Nine questions, a price and timeline band, and a brief you can keep. It runs in your browser, uses no AI, and starts with the answers set for this kind of product.
Questions
How much does a Chrome extension cost?
An extension that does one job on the page, with no accounts or outside services, runs $3,500 to $5,500 over about 3 to 4 weeks in my scope estimator. With sign-in and an outside API, or one AI feature, it reads as $6,500 to $9,000 over about 4 to 5 weeks.
Why does an API or AI cost more?
In the scope estimator, one or two outside services, or any AI feature, move the work to the $6,500 to $9,000 tier on their own. The extension then needs a small backend or secure calls, error handling, and testing against the real service.
What if I need a dashboard as well?
An extension plus a separate web app is two product surfaces, which my estimator treats as more than one sprint. The written scope splits it into sprints, usually the extension first, each with a fixed price.
Does the timeline include store review?
No. Google reviews every Chrome Web Store submission and sets its own timing. Deployment means submitting to the store from your own developer account. Review time is outside my control, so plan the launch date with some slack.
Who owns the extension and the listing?
You do. The code goes into a repository in your name and the listing sits on your own developer account, with a recorded walkthrough and 14 days of bug fixes after launch.
Is this page a quote?
No. It is a range from the same rules the scope estimator uses. A short written scope sets the fixed price, and you get one within 48 hours of sending a brief.