ClientSideTools Privacy-First Browser Tools

Storage Access API Tester

Third-party iframes lose access to cookies and storage under tracking prevention. The Storage Access API lets embedded content request its first-party storage back. This tester checks the current state and walks through the request flow with a real user gesture.

PWA & Browser Storage Local processing Runs entirely in your browser. Nothing is uploaded.

Tool interface

Introduction

Privacy features in modern browsers partition or block storage for cross-site iframes. Embedded widgets (login forms, payment, comments) that depend on cookies break unless they request storage access. This tester demystifies the API and its outcomes.

How it works

  • Detects Storage Access API support.
  • Reads the current state via document.hasStorageAccess().
  • Triggers document.requestStorageAccess() on a user gesture.
  • Logs the resolved (granted) or rejected (denied) result.

Privacy

All checks are local via the Storage Access API. No data leaves the browser. No account, no API key.

Limitations

  • Top-level pages usually already have storage access, so the interesting case is a cross-site iframe.
  • Behavior varies by browser and tracking-prevention settings.
  • Some browsers require prior user interaction with the embedded origin.

FAQ

Does requestStorageAccess always show a prompt?

Not always. If access is already granted or the browser's policy allows it, the Promise resolves without a prompt. Otherwise the browser shows a confirmation.

Is my data uploaded?

No. Everything runs locally in your browser.

Related tools

Version and changelog

  • Version: 1.0.0
  • Last updated: August 12, 2026
  • Changelog: Initial production release.