From the Files app
Use Open In or the share sheet to send a .html or .htm file to a compatible app.
iPhone and iPad
iOS does not include a general local HTML viewer. HTML Lens is built to open the file, render the page, show the source, and keep the document on your device.
Safari renders URLs, while Files relies on Quick Look for previews. A local HTML file can land between those systems without a built-in rendered preview.
Use Open In or the share sheet to send a .html or .htm file to a compatible app.
Open the attachment through the share sheet when a normal preview is unavailable.
Copy the full HTML and paste it into the free web tool or the native app.
Self-contained documents can render without uploading the file.
To render a local HTML file on iOS, use an app that registers for HTML documents and displays them in a WebView. If you only need to inspect the code, a text editor can open it as text, but it will not show the finished webpage.
Save the .html attachment to Files or copy the HTML from the place that created it.
Choose HTML Lens from the share sheet, or paste into the free web version.
See the page, inspect its source, and export it in the format you need.
Safari on iPhone is designed around web addresses and does not provide a normal File menu for opening arbitrary local HTML documents from Files.
Yes. A text editor can show a local HTML file as code. HTML Lens lets you move between source and the rendered page.
No. HTML Lens is local-first and does not upload your document to an HTML Lens server.
Responsive CSS, missing remote resources, or a missing viewport declaration can change how a page renders at phone width.