Storage Inspector
See exactly what this site has stored on your device — and why it cannot see any other.
How this test works
Local storage, session storage and the readable cookies for this origin are enumerated and listed with their sizes, alongside the storage quota the browser has offered. The important part is the scope, because “see what websites store about you” is almost always read as a promise to show everything, and no page can do that. Browser storage is partitioned by origin: this page can read what this origin wrote and nothing else — not another site's cookies, not your history, not your other tabs. Cookies marked HttpOnly are hidden even from this origin's own scripts, which is precisely why session tokens are set that way. Seeing everything a browser holds requires its own settings or developer tools, which sit outside the sandbox a page runs in.
What the results mean
- localStorage
- Persists until cleared. The usual home for preferences and cached data.
- sessionStorage
- Cleared when the tab closes. Scoped to this tab as well as this origin.
- Cookies (readable)
- Those JavaScript can see. HttpOnly cookies are excluded and are not counted.
- Scope
- This origin only. The single most misunderstood thing about browser storage.
Common problems and fixes
- It shows nothing but I know sites track me
- Correct, and it is the point. This page only sees its own origin. The trackers on other sites store data under their own origins, which no page can read.
- I want to see all my cookies
- Use the browser's own settings or developer tools. A page is confined to its origin by design and cannot enumerate the rest.
- Why can I not see my session cookie?
- It is almost certainly HttpOnly, which hides it from JavaScript entirely. That flag exists to stop scripts stealing session tokens.
Frequently asked questions
Can a website see cookies from other sites?
No. Storage is partitioned by origin and enforced by the browser. A page reads only what its own origin wrote, which is why this tool cannot show you anything else.
What is an HttpOnly cookie?
One the browser refuses to expose to JavaScript. It still travels with requests, so the server sees it, but no script on the page can read it. Session tokens use it to limit the damage from cross-site scripting.
Does clearing cookies clear everything?
Not necessarily. Local storage, IndexedDB and cache storage are separate, and browser interfaces vary in whether “clear cookies” includes them. Clearing all site data does.