Paste your HTML (or open an .html file), choose a phone size and orientation, and the page renders inside a phone frame at that exact CSS viewport. Nothing is uploaded — the preview runs in a sandboxed frame in your browser.
How to use it
- Paste a complete HTML document or open an
.htmlfile. - Pick a phone size. 360px wide is the single most common Android viewport; 412px covers most large phones.
- Switch to landscape for games and slides, and to dark to check your
prefers-color-schemestyles.
Why CSS pixels, not screen pixels
A phone with a 1080-pixel-wide screen and a device pixel ratio of 3 lays out pages at 360 CSS pixels. Your media queries, and the WebView inside your app, use CSS pixels — so that is what this preview uses. The Android viewport sizes page lists the common ones.
What to check
- Nothing scrolls sideways at 320px.
- Buttons are comfortably tappable — run the touch target checker.
- Text is readable without zooming (16px body minimum).
Happy with it? Follow the step-by-step guide to build the APK.
Frequently asked questions
Does this upload my HTML?
No. The preview uses an iframe's srcdoc in your own browser. Nothing is sent to a server.
Is this exactly how my app will look?
Very close — Android WebView uses the same Chromium engine as Chrome. Differences come from the app shell: status bar colour, safe areas and system font.