What you can make
Cut a short product demo, tutorial or sharing clip from a browser-supported MP4, MOV or WebM. Output is a new WebM file, not the original codec or container. Export takes roughly as long as the selection.
LOCAL VIDEO EDITOR
Video Cutter Online
Your original file stays unchanged. Previews start muted.
Choose the moment you need. Set the start and end, preview your selection, then download a WebM clip.
Files stay in this browser
WebM-only output
Input up to 100 MiB / 10 min
Clips up to 60 seconds
Productivity
MP4, MOV or WebM input where your browser can decode it. Output is WebM, not frame-exact editing.
Video Cutter Online Choose a short video, set the range, preview silently and create a new WebM clip. The original file stays unchanged.
What this tool does
- local MP4, WebM, and MOV preview
- start and end time controls with millisecond fields
- selection preview before export
- truthful MediaRecorder-based WebM-only export where supported
- hard 100 MiB source, 10 minute source and 60 second selection limits
- no FastTool application upload or account required
- exact source/output SHA-256, byte length and media type
- stale-download lock plus cancel/reset
- downloadable JSON and Markdown receipts
- fail-closed result when the browser cannot encode and hash WebM
What can I edit?
Short practical media jobs
Choose the part you need, preview it silently, then export a checked WebM. Your source file is unchanged. Export takes roughly as long as the selected clip.
- Social clips
- Product demos
- Tutorial snippets
- Short clips for sharing
Formats, limits and privacy
Checks before download
The selected range must complete at normal speed. The generated WebM is reopened to check its dimensions and duration before downloads become available. Source or range changes lock the previous download. Replay the current clip before sharing; optional verification files contain exact byte lengths and hashes.
Your video stays local
Video bytes, filenames, selected timestamps and hashes stay in this browser tool. Allowlisted analytics do not receive them. Use non-sensitive clips and a trusted device; avoid confidential meetings, private footage, unreleased campaigns and regulated recordings.
Know the limits
Maximum source: 100 MiB and 10 minutes. Maximum selection: 60 seconds. This is real-time re-encoding, not frame-exact editing or a guarantee of audio/video sync. No MP4 export, codec preservation, DRM processing or legal-evidence certification. Browser codec and recording support are required.
Try a sample and check the result
Try the built-in four-second synthetic video without choosing a personal file. Select the range you need, preview it silently, then create and replay the WebM.
Sample input
A clearly labeled synthetic four-second WebM fixture generated locally in the browser. It is not customer footage or a real-world claim.
Expected output
A replayable WebM-only artifact with exact source/output SHA-256, byte length, media type, receipt-core hash, and downloadable JSON and Markdown receipts.
Proof checks
- Checks actual video preview and export path, not only a file picker.
- Selection range, WebM media type, exact bytes, source/output hashes and replay are visible after export.
- Changing the source or range locks stale WebM and receipt downloads.
- Cancel/reset creates no valid artifact; unsupported WebM or SHA-256 capability fails closed.
When not to use it
Not for feature-length files, legal evidence, codec-preserving broadcast work, DRM media, or exact frame-accurate professional editing.
Privacy boundary: Video bytes stay in the browser workflow. Tool analytics use only allowlisted lifecycle events and never include raw input, filename, hashes, selected timestamps, or video bytes. Do not use regulated or confidential media on an untrusted device.
Questions before you cut
How do I cut a video online?
Choose a local video, set the start and end time, preview the section, then create a trimmed WebM copy. Replay and download the current result. Verification files are optional.
Does my video get uploaded?
The standard workflow uses your browser file APIs and does not upload the video to a FastTool application server.
Why is the output WebM?
This tool only exports a real-time re-encoded WebM where the browser exposes a supported MediaRecorder codec. MP4 or MOV input never implies MP4/MOV output or codec-preserving editing.
What is the hard file limit?
The source must be at most 100 MiB and 10 minutes; the selected export must be at most 60 seconds. Unsupported decoding, WebM encoding, capture, or SHA-256 capability fails closed.
Will export play sound through my speakers?
No. Export uses an isolated audio path that does not connect to your speakers. The source and result previews start muted; you can deliberately unmute a preview using its video controls.
Why did an incomplete export stop instead of downloading?
A stalled source, invalid range or output that cannot be decoded is not a finished clip. Keep the tab visible, check that the source plays correctly and try a shorter selection. This real-time browser export is not frame-exact editing; check the first and last frames and audio sync before sharing.
How it works and reference sources
This Video Cutter uses File, HTMLMediaElement, captureStream, MediaRecorder and Web Crypto. It performs a real-time WebM re-encode, then hashes the exact source and output bytes. It does not claim MP4 output, codec preservation, exact-frame cutting, legal evidence, or universal browser support.