Storage Test
Verify localStorage, sessionStorage and IndexedDB work, read your storage estimate, and time small operations.
This checks that browser storage works and roughly how fast small operations are — it is not a physical disk-health test. All test keys are removed afterward.
How this test works
System and browser tests read information your browser already exposes through standard APIs — the navigator and screen objects, feature detection, and capability queries such as WebGL, WebGPU and the Permissions API.
No permission prompts are triggered by simply viewing these pages, and nothing is combined into a tracking identifier. Where a value is approximate because of privacy protections (like User-Agent reduction), we say so.
Capability detection tells you whether an API exists in this browser; actually using some of those APIs may still require your explicit permission or a secure context.
How to use it
- Open the test — most system tests read values immediately with no permission needed.
- Review the reported information or capability matrix.
- Use search or filter where provided to find a specific feature.
- Copy or download the results if you want to share them (they contain no hidden identifier).
What it detects
- Browser-exposed device details: platform, screen, cores, memory hint, languages and time zone
- Support for storage, graphics, media, worker and sensor APIs
- WebGL/WebGPU renderer details where the browser exposes them
- Battery, storage estimate and network information where available
What it can’t detect
- Exact hardware model, serial numbers, or anything deliberately hidden for privacy
- Physical component health (battery capacity, disk wear) — browsers don’t expose it
- Values reduced by the browser, such as a precise User-Agent or full GPU string
Troubleshooting
| Symptom | What to do |
|---|---|
| Some info is missing | Modern browsers intentionally limit what they expose (User-Agent reduction and similar) to protect your privacy. |
| A feature shows unsupported | The API doesn’t exist in this browser/context; try a recent version over HTTPS. |
| WebGL renderer is hidden | Some browsers mask the GPU string for privacy; that’s expected, not an error. |
| Battery API shows nothing | Several browsers removed the Battery Status API for privacy; use your OS indicator instead. |
FAQ
Do you fingerprint me?
No. We show information but never build a hidden cross-session fingerprint or hash.
Why is some info missing?
Modern browsers intentionally limit what they expose to protect your privacy.
Is this data sent anywhere?
No. It’s read and displayed locally in your browser.
Does ‘supported’ mean I can use the feature?
It means the API exists. Using it may still require permission or a secure (HTTPS) context.
Why doesn’t it show my exact GPU or browser version?
Browsers increasingly reduce these details for privacy, so some values are approximate.
Can this test my hardware’s health?
No. Browsers don’t expose battery capacity, disk wear, or similar health metrics.
Related tests
Write, read and delete a first-party cookie to confirm cookies work, with a SameSite explanation. No tracking iframe.
A searchable matrix of Web API support — supported, unsupported or permission-required — with no automatic prompts.
Check service worker, manifest, standalone mode, cache storage and offline readiness for Progressive Web Apps.