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Online Video Editor (Timeline, Trim, Text & Music)

Edit video in your browser on a multi-track timeline: trim, split, speed, fades, filters, transitions, titles, logos and music, then export WebM or a WAV mix. Files never leave your device.

Overview

A timeline video editor that runs entirely in your browser tab. Import MP4, WebM or MOV clips, MP3, WAV or M4A music and still images, arrange them on two video tracks and two audio tracks, then trim, split, change speed, add titles, a logo watermark and transitions. Export a WebM file, a WAV mixdown or a PNG still without uploading anything.

How It Works

Drop files into the media bin and each one is probed for duration, size and a thumbnail; sound files also get a waveform. Drag a file onto a track or press Add to place it at the playhead. Drag a clip body to move it, drag either edge to trim, and press S to split at the playhead. Clips snap to neighbouring edges, markers and the playhead. The inspector on the right holds speed, volume, fades, position, scale, rotation, crop, colour filters, the transition into the clip and text styling for titles.

Step-by-Step Usage Guide

  1. Import video, audio and image files into the media bin, or drop them on it.
  2. Drag clips onto the V1, V2, A1 and A2 tracks and arrange them; snapping lines clips up end to end.
  3. Trim edges, split with S, delete with Delete or close gaps with Shift+Delete for a ripple delete.
  4. Select a clip to set speed, volume, fades, crop, filters, a crossfade or slide transition, or title text.
  5. Pick a size preset such as 1080 p, vertical 9:16 or square, a frame rate and a bitrate.
  6. Click Export video for a WebM file, or Export audio for a WAV mix of every track.

Technical Specifications & Standards

The preview is a canvas redrawn on every animation frame. Each video clip gets its own hidden video element that plays at the clip speed and is re-seeked whenever it drifts more than a quarter of a second from the timeline clock, and its sound is routed through a Web Audio gain node so clip volume, track volume and fades are applied live. Export uses the same compositor. When the browser offers WebCodecs, the editor seeks every layer to the exact time of each output frame, draws it, and hands the canvas to a VideoEncoder for VP9, VP8 or AV1; audio is mixed sample by sample in JavaScript and encoded to Opus with AudioEncoder. A small Matroska writer built for this tool packs both streams into a WebM file with clusters that start on keyframes and a cue index for seeking. Browsers without those encoders fall back to canvas.captureStream with MediaRecorder, which records in real time. The project JSON autosaves to IndexedDB and imported files are copied into the Origin Private File System, so a reload brings the edit back.

Targeted Use Cases

  • Cutting a screen recording down to the useful parts and adding a title card before sharing it with a team.
  • Making a vertical 9:16 short from landscape footage with captions placed in the lower third.
  • Laying background music under a voice clip and fading it out at the end.
  • Stamping a semi-transparent logo in a corner of a product demo as a watermark.
  • Joining several phone clips with crossfades into one video for family or a client.

Notes & Gotchas

  • Butt clips together on the same track before choosing a transition; the effect only plays when the previous clip ends exactly where the next one starts.
  • Use Chrome or Edge for the frame-accurate WebCodecs export; other browsers may record in real time instead.
  • Keep source files under a few gigabytes in total, since the browser holds decoded audio for the mix in memory.
  • Export a WAV mix first if you plan to finish the sound in a separate audio program.

Frequently Asked Questions

Are my videos uploaded anywhere?

No. Files are read by your browser, stored in its private storage on this device for autosave, and every export is rendered locally. Nothing leaves the computer unless you share the exported file yourself.

Which file formats can I edit?

Anything your browser can decode: usually MP4 with H.264 and AAC, WebM with VP8, VP9 or AV1, and MOV files that use H.264. Audio can be MP3, WAV, OGG, M4A or FLAC, and images can be PNG, JPEG, WebP or GIF. A file the browser cannot play is rejected with a message at import.

Why is the export WebM instead of MP4?

WebM is the container the editor writes itself from WebCodecs output, so it works the same in every supporting browser. The real-time recorder fallback may produce MP4 in Safari. Most players, YouTube and social sites accept WebM; convert it afterwards if a service insists on MP4.

How does the speed setting change a clip?

Speed runs from 0.25x to 4x. The clip keeps the same source in and out points, so its length on the timeline becomes the source length divided by the speed, and later clips on that track are pushed right if it grows. Sound is resampled, so pitch rises and falls with speed.

What happens if I clear my browser data or move to another device?

The project and media live only in this browser's storage. If stored media is missing when you reopen the editor, the bin marks it and offers Re-link so you can point at the original file again. Projects do not sync between devices.

Related tools

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