About DisplayProbe

Who runs this

DisplayProbe is an independent project that builds browser-based display tests and documents what a browser can and cannot measure. It is funded by nobody, sells nothing, and has no relationship with any display manufacturer.

You can reach a person at [email protected]. There is no contact form, because a form needs a server and this site does not have one.

Why it exists

Most screen-testing sites claim things a web page cannot do: "automatic dead pixel detection", brightness readings in nits, contrast ratios, colour accuracy figures, panel technology verdicts. None of those are available to a browser. There is no API that reports what light your panel is emitting, and there is no way to fake one.

That matters because a fabricated number sends you the wrong way. If a site tells you your contrast ratio is fine while your blacks look grey, you start doubting your own eyes instead of checking the RGB range setting that is actually causing it. And once a tool has told you something demonstrably untrue, you have no way to judge which of its other claims are real.

So this site does the opposite. Every tool states what it measures, every measurement is tied to a documented technique, and everything that is a judgement call is labelled as one. The full list of what is and is not possible lives on what a browser cannot detect, and the techniques are written up on the methodology page.

The rules this is built to

• Never claim a measurement a browser cannot make. Every user-facing claim is recorded against a capability tier, and a build-time scan fails the release if a forbidden pattern appears in any page.
• Never invent numbers or social proof. No fabricated statistics, no invented review counts, no testimonials, no made-up manufacturer thresholds. Where a figure appears it is attributed, and where a source could not be verified the sentence was cut.
• Every tool works. There are no buttons on this site that do nothing.
• Every tool carries a visible limitations block. Not collapsed, not in a footnote, and written like a knowledgeable friend rather than a lawyer.
• What you test stays on your device. No accounts, no cookies, and no server that could receive a result even if one were sent.
• Point elsewhere when elsewhere is better. Blur Busters for motion science, Lagom for calibration patterns, hardware reviewers for measured specifications.

How it is built

Static HTML, CSS and a small amount of TypeScript, generated ahead of time and served as plain files. There is no database, no backend and no runtime API. The measurement code is framework-free and unit tested, and after your first visit a service worker keeps the whole toolset working with no network connection at all, useful when you are checking a screen in a shop, a storeroom, or someone's front room.

What it costs

Nothing to use, and there is no paid tier. Running the site costs money, so advertising may be added to cover it. If that happens, the privacy page will be updated before it goes live and the changelog will record the date. Advertising will not change what the tools measure or what the pages say about their limits.

Corrections

If something here is wrong, say so. Corrections are made and recorded in the changelog, which is the most useful message anyone can send.