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WebM to MP4 Converter

Convert WebM videos, often downloaded from the web, into the universally supported MP4 format. While WebM is excellent for browsers, many devices like iPhones and smart TVs lack native support; this tool ensures your videos play everywhere with optimal quality, suitable for sharing and offline viewing.

check_circleiPhone Compatible check_circleHigh Quality check_circleNo Watermark
video_file

Drop your WebM file here

or click to select file

Supports WebM files - Max 500MB (Pro: 2GB)

Why Convert WebM to MP4?

WebM excels in browsers, but most devices, editors, and platforms still expect MP4.

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iPhone & iPad Support

Apple devices don't natively support WebM. Safari, the Photos app, iMessage, and AirPlay all reject WebM files. Converting to MP4 with H.264 enables seamless playback on every iPhone, iPad, Apple TV, and Mac without third-party apps or codec installations.

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Smart TV Playback

Most smart TVs from Samsung, LG, Sony, and Roku support MP4 but have limited or no WebM support. Converting lets you watch browser-downloaded videos on your living room screen via USB drive, DLNA streaming, or built-in media players.

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Video Editing Compatibility

Professional editors like Adobe Premiere Pro, DaVinci Resolve, and Final Cut Pro work best with MP4 input. WebM import is inconsistent — some versions support it, others don't. Converting screen recordings or web downloads to MP4 before editing prevents timeline errors and render failures.

How to Convert WebM to MP4

1

Upload WebM File

Drag your WebM file into the upload area or click to browse. We accept WebM files with VP8, VP9, or AV1 video codecs and Vorbis or Opus audio. Maximum 500MB for free users, 2GB for Pro accounts.

2

Choose Quality

Choose your preferred quality tier. High Quality re-encodes with H.264 High Profile for maximum fidelity. Balanced uses Main Profile with optimized bitrate for the best size-to-quality ratio. Compressed creates compact files ideal for email attachments and messaging apps.

3

Download MP4

Our cloud servers transcode your WebM to MP4 using hardware-accelerated H.264 encoding with AAC audio. Download the result and play it on any device — iPhone, Android, smart TV, game console, or media player.

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Frequently Asked Questions

Common questions about WebM to MP4 conversion.

Why do browsers save videos as WebM?

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WebM is royalty-free, meaning browser vendors don't pay licensing fees to use it. Google championed WebM as the open alternative to H.264 (which requires patent licenses). Chrome, Firefox, and Edge all support WebM natively, and many web-based tools — screen recorders, video editors, and conferencing platforms — default to WebM because it avoids licensing complexity. This is why downloaded web videos are often in WebM format.

What's the difference between VP8, VP9, and AV1 in WebM?

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VP8 (2010) was the original WebM codec — roughly comparable to H.264 in quality and compression. VP9 (2013) improved compression by 30-50%, making it competitive with H.265/HEVC, and is used extensively by YouTube for 4K streaming. AV1 (2018) is the newest generation, offering another 30% improvement over VP9, but requires more processing power to encode and decode. Our converter handles all three seamlessly.

Can I upload WebM files to social media?

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Most social media platforms either don't accept WebM or transcode it with quality loss. Instagram, TikTok, and X (Twitter) prefer or require MP4. YouTube accepts WebM but may re-encode it. Facebook has limited WebM support. Converting to MP4 before uploading gives you control over quality settings and ensures the platform accepts your file without additional processing.

Does WebM support subtitles and chapters?

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WebM, based on the Matroska container, technically supports subtitle tracks and chapter markers. However, most tools that create WebM files don't include these features, and most players ignore them in WebM. MP4 has more robust subtitle support (SRT, SSA) and chapter support recognized by QuickTime, VLC, and hardware players.

How do I convert a WebM file from a web page?

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If you've downloaded or saved a WebM video from a website, simply upload the .webm file here using drag-and-drop or the file browser. The source doesn't matter — whether it's from a screen recording, a downloaded HTML5 video, a video call recording, or an exported clip from an online editor, our converter processes all valid WebM files identically.

Is WebM the same as MKV?

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WebM is technically a subset of MKV (Matroska). Both use the same container structure, but WebM restricts the allowed codecs to VP8/VP9/AV1 for video and Vorbis/Opus for audio. MKV can contain virtually any codec combination. You can often rename a .webm file to .mkv and it will play in MKV-compatible players, though the reverse isn't always true.

Understanding the WebM Format

WebM was born from Google's acquisition of On2 Technologies in 2010 for $124.6 million. On2 had developed the VP8 video codec, which Google open-sourced and paired with the Matroska container and Xiph.org's Vorbis audio codec to create WebM — a completely royalty-free video format designed for the open web. The goal was ambitious: provide a patent-free alternative to H.264, which requires licensing fees through the MPEG LA patent pool, and make high-quality video accessible to every web developer without legal barriers.

The format evolved significantly with VP9 in 2013, which YouTube adopted for its 4K and HDR content delivery. VP9 offered compression efficiency comparable to H.265/HEVC while remaining royalty-free. By 2020, YouTube served over 75% of its content in VP9-encoded WebM format. The latest evolution, AV1 (developed by the Alliance for Open Media — including Google, Mozilla, Microsoft, Apple, and Netflix), pushes compression further while maintaining the royalty-free philosophy. WebM files with AV1 are increasingly common on modern websites.

Despite its technical merit and adoption by major web platforms, WebM's Achilles heel remains device compatibility. Apple never added native WebM support to iOS or Safari until limited support arrived in late 2023, and even now, it's inconsistent across Apple devices. Most smart TVs, game consoles, and embedded media players lack WebM support. This compatibility gap is why converting WebM to the universally supported MP4 format remains essential for anyone who needs their videos to work everywhere — not just in web browsers.

Privacy & Security

Your videos are processed securely. We take your privacy seriously.

  • check_circleAutomatic Deletion: All uploaded WebM files and converted MP4 files are permanently deleted within 24 hours.
  • check_circleEncrypted Transfer: Files are uploaded and downloaded over HTTPS with TLS 1.3 encryption.
  • check_circleNo Human Access: Conversion is fully automated. No one views, analyzes, or shares your video content.