Free online SWF to HTML converter

Current browsers no longer include Flash Player, so legacy .swf games, animations, training modules, and banners need an HTML-based page for web delivery. The result may be an HTML wrapper that runs the original SWF through an emulator, or a rebuilt HTML5 application when the source project is available.

What the SWF format is

SWF is Adobe Flash’s compiled binary delivery format. It can contain vector artwork, bitmap images, fonts, timeline animation, audio, video, buttons, and ActionScript code.

Adobe Flash Professional, later renamed Adobe Animate, produced SWF files from editable .fla projects; Apache Flex also produced SWF applications. Legacy websites, e-learning packages, browser games, advertisements, help systems, and archived interactive media commonly contain SWF files.

An SWF is normally not the editable source. The original .fla or .xfl project is much more useful for a native HTML5 rebuild because it retains timeline structure, library assets, and authoring information.

What the HTML format is

HTML is the text-based markup format that defines the structure of a web page. An .html file can reference JavaScript, CSS, images, fonts, audio, video, Canvas, SVG, WebGL, and other supporting files.

HTML runs in current browsers without a Flash plug-in and can be hosted on a standard web server, embedded in an existing site, and shared by URL. For former Flash content, HTML is usually the delivery layer for an emulator or for replacement JavaScript and media assets.

HTML does not natively execute ActionScript or decode SWF content. A published result can therefore be an emulator-backed page, extracted assets, video, or a manually rebuilt web application rather than a direct translation into editable HTML and JavaScript.

Convert an SWF file to HTML

For a browser-viewable output package, upload the .swf file to the free converter on 101convert.com, select HTML output, and download the generated files. Keep the downloaded HTML file, JavaScript files, asset folders, and any retained SWF file together; moving only index.html usually breaks the page.

Test the output in a current browser, including menus, buttons, keyboard input, sound, video, forms, and navigation. If opening the HTML file directly causes blocked assets or WebAssembly errors, serve its folder locally:

python -m http.server 8000

Then open http://localhost:8000. Upload the complete output folder to a web server for public use.

Use the original project when available

When an editable .fla or .xfl file exists, use Adobe Animate rather than converting the compiled SWF. Open the project and use File → Convert To Other Document Formats → HTML5 Canvas where applicable, then configure output in File → Publish Settings and select File → Publish.

Animate HTML5 Canvas documents use JavaScript and CreateJS. ActionScript 2 or ActionScript 3 code, Flash components, video objects, filters, and some blend modes do not convert into working browser code automatically; rebuild those functions with JavaScript and standard web APIs. Deploy the generated HTML, JavaScript, image, font, and media files as one package.

Preserve a published SWF with Ruffle

When only the compiled SWF remains, Ruffle is usually the most practical way to retain interactivity. Ruffle is an open-source Flash emulator compiled to WebAssembly; an HTML page loads Ruffle and the original .swf, so the SWF remains part of the deployment instead of becoming editable JavaScript.

Download Ruffle’s self-hosted web build, place its files beside the SWF, and use the project’s current self-hosting embed template in an HTML page. Set the SWF path and the intended display dimensions, then test from an HTTP or HTTPS server rather than a file:// URL.

Compatibility and quality limits

Ruffle compatibility varies by Flash version and runtime. AVM1 content, commonly associated with older ActionScript 1 and 2 files, is generally more mature than AVM2/ActionScript 3 support. Content using unsupported APIs, proprietary video codecs, webcams, microphones, DRM, local shared objects, browser integrations, or unavailable server endpoints can fail or behave differently.

Exporting an animation as MP4 or WebM can preserve visible motion and audio, but removes games, quizzes, buttons, input fields, and ActionScript logic. Use this option only for content that does not need interaction.

Tools such as JPEXS Free Flash Decompiler can inspect a SWF and extract images, sounds, fonts, and scripts for a manual rebuild. Decompiled ActionScript may be incomplete or difficult to maintain and does not restore the original authoring project.

Test the final page in the target desktop and mobile browsers. Replace HTTP-only media or data endpoints before publishing on an HTTPS site, because browsers block mixed-content requests.