Most of the cost sits behind the extension
A browser extension is rarely expensive because of its interface. Cost accumulates in what the extension touches: the pages it reads, the permissions it requests, the account model it authenticates against, and the platform that stores and reports on what it captured.
At Wibolabs, a focused Chrome extension paired with a web platform begins at AUD 4,900. A standalone single-purpose extension with no backend is smaller; a multi-role platform with billing, tenant isolation, and integrations is estimated separately.
The real cost drivers
Two extensions with identical popups can differ by an order of magnitude once the underlying workflow is included.
- Number of sites the extension must reliably read or modify
- How often those sites change their markup
- Permissions requested and the justification Chrome will require
- Authentication, roles, and shared team state
- Offline behaviour, sync, and conflict handling
- Manifest V3 service-worker constraints and background work
Budget for review, not just build
Chrome Web Store review is a real delivery stage. Broad host permissions, remote code, and unclear data handling are the common causes of rejection or extended review, and each round trip costs days.
A responsible quote includes the privacy policy, permission justification, store listing assets, and at least one review cycle. Extensions quoted without these are usually quoted incompletely.
Where to spend and where to stop
Spend on the permission model, the data boundary, and the reliability of the pages you depend on. Postpone extra browsers, deep customisation, and speculative automation until the first workflow is proven in daily use.
Snapraven is a useful reference for how far real-browser evidence can be pushed when the capture layer and the reporting platform are designed together rather than bolted to each other later.