Free online HTM to WEBP converter

Some image workflows and web publishing systems require a rendered page image rather than an HTML document. Converting an HTM file to WEBP captures the page’s visible layout as a compressed raster image for sharing, previews, thumbnails, or storage.

What the HTM format is

HTM is an HTML webpage file; the three-letter extension is functionally equivalent to .html. It contains markup for structure and text, while CSS, JavaScript, images, fonts, and other resources may be stored in separate files or loaded from the internet.

Web browsers such as Chrome, Edge, Firefox, and Safari open HTM files. Web editors, content-management systems, documentation tools, and page-saving features can create them. An HTM file commonly appears in downloaded webpages, offline documentation, exported reports, and local website projects.

What the WEBP format is

WEBP is a raster image format designed for web delivery. It supports lossy and lossless compression, transparency, and animation; a WEBP file stores pixels rather than editable HTML structure.

WEBP usually produces smaller files than JPEG or PNG at comparable visual quality. Use it for page previews, browser images, thumbnails, and other cases where the rendered appearance matters more than selectable text, links, scripts, or responsive behavior.

How to convert HTM to WEBP

Using the built-in online converter

1. Open the HTM-to-WEBP converter on 101convert.com; it is available for free without installing software.
2. Select or upload the .htm file. If the page depends on local CSS, images, fonts, or scripts, place those resources with the HTML file and use the converter’s supported upload method when available.
3. Start the conversion and wait for the rendered result.
4. Download the resulting .webp file.

The converter renders the page as an image; it does not preserve HTML text, links, forms, JavaScript behavior, or a reusable stylesheet.

Using a Chromium browser locally

For a one-off screenshot, open the file in Chrome or another Chromium-based browser with file:///path/to/page.htm, set the required viewport and zoom, open DevTools with F12, choose the device toolbar if needed, then use the DevTools command menu and select Capture full size screenshot. Chromium commonly saves a PNG, which can be converted to WEBP with an image editor or ImageMagick:

magick page.png -quality 85 page.webp

For repeatable command-line rendering, Chromium can capture a viewport screenshot directly:

chromium --headless --disable-gpu --screenshot=page.png --window-size=1440,900 file:///absolute/path/page.htm

Convert the captured PNG with the same ImageMagick command. Use a larger --window-size for wider layouts; full-page capture behavior varies by Chromium version, so the browser’s full-size screenshot command is preferable when the page extends below the viewport.

Quality, compatibility, and limitations

• The output depends on the browser rendering the HTM file. Missing local assets, blocked external resources, unavailable web fonts, JavaScript errors, and network restrictions can change the image.
• WEBP dimensions are determined by the capture viewport or converter settings. A narrow viewport may trigger mobile CSS, while a wide viewport may produce a different layout.
• Use lossless WEBP when small text, line art, or sharp UI elements must remain exact; use lossy quality around 80–90 for photographs or ordinary page previews. Lossy compression can blur text and thin borders.
• A long HTM page may be exported as one tall image, a cropped viewport, or separate images depending on the tool. WEBP has no native concept of HTML pages or multiple page sections.
• Most current browsers support WEBP, but older applications may require PNG or JPEG. If compatibility is uncertain, retain the original HTM and use WEBP only as the delivery or preview copy.