WebM Cutter

How to Cut WebM Video Online

1. Upload Your WebM File: Drag and drop or click "Add Files" to select WebM files from OBS recordings, browser screen captures, downloaded YouTube clips, or Twitch VODs. Batch is supported — drop in several files and apply the same cut range to each.
2. Set Start Time and Duration (VIDEO_TRIM): Enter a start time and a duration to keep. Both fields accept seconds (12.5) or HH:MM:SS.sss format (00:01:30.500). Add multiple trim segments to extract several clips from one source — each pair produces its own output file.
3. Choose Codec and Quality (Optional): By default the cut is frame-accurate and the video is re-encoded at the visually-lossless default preset, keeping WebM as the container. For a smaller file or a different codec, pick VP9 (CRF 0-63, default 31), AV1 (CRF 0-63, slower but ~30% smaller than VP9), or VP8 (legacy compatibility). Resize to 1080p / 720p / 480p / 360p / 240p or scale by percentage.
4. Cut and Download: Click Cut. Files process on our servers — download individually or as a ZIP. No sign-up, no watermark, no sign-up.

Why Cut WebM Files?

WebM is the open, royalty-free container Google built for HTML5 video — VP8 / VP9 / AV1 video paired with Opus or Vorbis audio. It's the default output for most browser-based screen recorders, OBS Studio's lightweight option, yt-dlp's preferred download format for YouTube, and the format Discord uses for animated stickers. Cutting WebM is useful for:

• Trimming OBS recordings — OBS often ships hour-long sessions when you only wanted the 30-second highlight. The cut processes just the segment you keep, re-encoded at the visually-lossless default preset.
• Browser screen capture excerpts — Chrome's MediaRecorder API, Loom downloads, and most WebRTC capture extensions output WebM. Cut down a 20-minute walkthrough to the 90-second portion that actually demonstrates the bug.
• Downloaded YouTube and Twitch clips — yt-dlp pulls YouTube as .webm (VP9 + Opus) by default. Trim to the exact moment of a goal, joke, or game-winning play without converting first.
• Social platform length caps — Instagram Reels: 90s. TikTok: 60s for max engagement. YouTube Shorts: 60s. X video: 2:20. Cut the WebM down to fit before uploading so the platform doesn't auto-chop the wrong moment. (Most platforms re-encode on upload anyway, so the visually-lossless cut here costs nothing you'd keep.)
• Discord and chat sharing — Discord's free 10 MB / Nitro Basic 50 MB caps mean a 5-minute WebM at decent bitrate won't fit. Cut to the 20-second clip you actually want to share.
• Removing bloated intros and dead air — Strip the 10 seconds of black screen at the start of an OBS capture, the long pause before a Zoom recording started, or the show's title card from a downloaded VOD.

For a different output container after cutting, see WebM to MP4 or WebM to GIF.

Default Cut vs Custom Settings — When to Use Which

Property	Default settings	Custom settings (VP9 / AV1 / VP8)
Speed	Proportional to clip length	Proportional to clip length and codec
Quality	Re-encoded at the visually-lossless default preset	Whatever CRF you choose
Cut precision	Frame-accurate	Frame-accurate
Output codec	Standard codec in WebM	Any: VP9, AV1, VP8
Audio	Re-encoded (Opus by default) at a matching bitrate	Re-encoded to the codec you pick
File size	Proportional to duration kept	Variable by CRF / bitrate
Best for	Quick extraction at source-matching quality	Smaller file, codec change, different resolution

Either way the cut is frame-accurate: whether you need "minutes 2-5 of this 20-minute screen recording" or the exact frame a button was clicked or a goal was scored, the kept segment is decoded and re-encoded so it starts precisely where you say.

WebM Codec Quick Guide

Codec	CRF Range	Default	Use Case
VP8	4-63	10	Legacy WebM, broadest browser support pre-2017
VP9	0-63	31	Modern WebM, YouTube's default, ~50% smaller than VP8
AV1	0-63	30	Newest, ~30% smaller than VP9, slower to encode
Opus (audio)	—	128 kbps	Default WebM audio, best quality-per-bit below 128 kbps
Vorbis (audio)	—	128 kbps	Legacy WebM audio, kept for compatibility

Lower CRF = higher quality and larger file. CRF 23 is a typical "visually lossless" target for VP9; CRF 30 for AV1 produces similar visual quality at smaller size.

Frequently Asked Questions

Will the cut WebM still play in Chrome, Firefox, and Discord?

Yes. The cut keeps WebM as the container with a standard VP8/VP9 stream and Opus/Vorbis audio — if it played in Chrome before the cut, it plays after. WebM has been natively supported in Chrome, Firefox, Edge, and Opera since 2010; desktop Safari added partial WebM support in 14.1 (macOS Big Sur, 2020) and full support in 16.0; iOS Safari gained full WebM support in 17.4. Discord renders WebM inline on every platform.

My WebM is from OBS — does cutting preserve the audio sync?

Yes. Video and audio are re-encoded from the same start offset, so any sync that was correct in the source stays correct in the output. The only situation where sync drifts is if the source itself had drift (some long OBS captures with VFR), in which case re-encoding to a constant frame rate often fixes it.

Why does the cut start a few seconds earlier than I asked for?

With XConvert it shouldn't — the cut re-encodes the kept segment, so it starts at your exact timestamp. The snap-back you're describing is how stream-copy cutters behave: they can only cut at keyframes (I-frames), and most WebM encoders place keyframes every 5-10 seconds, so those tools rewind a requested 00:01:23 cut to 00:01:18. Here the cut lands exactly on 00:01:23.

Can I extract just the audio (Opus / Vorbis) from the cut?

Yes — use WebM to Opus or WebM to OGG instead, which extracts the audio stream during the conversion. For an MP3 or WAV instead, see WebM to MP3 or WebM to WAV.

What's the maximum WebM file size or length?

There's no fixed cap. Cutting runs on our servers, so the practical limit is upload size and connection speed and how patient you are with the file load. Multi-GB OBS captures and 4-hour Twitch VOD downloads work fine. Processing time scales with the length of the segment you keep, not the full source duration.

Can I make multiple cuts from one WebM in a single pass?

Yes. Add multiple trim segments — each pair of start time + duration produces a separate output clip. Useful for pulling several highlights from a long stream, splitting a lecture recording into chapters, or extracting every appearance of a specific player from a sports VOD.

Should I cut first or convert WebM to MP4 first?

Cut first, always. Cutting only processes the segment you keep, which shrinks the file before the slower conversion step. A 5-minute clip pulled from a 60-minute WebM transcodes to MP4 far faster than transcoding the full hour and trimming the MP4 afterward. See WebM to MP4 for the conversion step.

Does cutting remove the audio track?

No, by default the output keeps both the video and the audio track. If you specifically want a silent clip (for over-dubbing, looping background, or a muted social post), set the audio codec option to "no audio" before cutting. The output will be a video-only WebM.

What's the difference between cutting and trimming a WebM?

Same operation in practice. Some editors reserve "trimming" for shaving the start and end of a clip while keeping the middle, and "cutting" for extracting a middle portion or splitting at a point. XConvert's cutter handles all three patterns — set start time to your in-point and duration to how much to keep. See also WebM Trimmer for the same workflow framed slightly differently.