RUNWEBTOOLS
English

Video Editor

Trim, split, merge, and caption video right in your browser — join clips, add text and music, change speed, no upload and no watermark.

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Examples

Cut a 10-second highlight

Output

Drag the start handle to 0:05 and the end handle to 0:15, then Export MP4 → a 10-second clip with the original audio, exported in seconds.

Trim a dead intro off the front

Output

Drag the start handle past the boring intro. The exported video begins exactly where you set the start point — no re-encoding, no quality loss.

Cut a mistake out of the middle

Output

Scrub to the start of the bad part and press Split, scrub to the end and Split again, then delete the middle clip. Export joins the two good halves into one seamless MP4.

Reorder two moments

Output

Split the clip in two, then use the ← / → arrows on a clip card to swap their order. The export plays them in the new order.

Merge two separate videos

Output

Load the first video, click Add video to bring in the second, then Export & join MP4 → one file with both clips back-to-back, resized and re-timed to match automatically.

Add a title caption

Output

Select the clip, click Add text, type your title and drag it into place. Set it to show for the first 2 seconds, then export → the caption is burned into the MP4.

Make a music montage

Output

Add a few clips, set some to 2× for a fast-forward feel, click Add music and mute the original audio, then export → a clean montage cut to your track.

About this tool

This free online video editor lets you trim, cut, split, join, merge, caption, speed up, and add music to video right in your browser — no upload, no account, and no watermark. Load one clip or several, set the start and end points on the timeline, split at the playhead, add text captions, change each clip's speed, lay a music track underneath, reorder or delete the pieces you don't want, and export a clean MP4.

How to use

  1. Choose one or more videos or drag them onto the drop zone (never uploaded).
  2. Press Play to preview, or click the timeline to scrub.
  3. Drag the start and end handles to select the part you want to keep.
  4. Move the playhead and press Split to break the clip into pieces.
  5. Click Add video to merge in more files — each becomes a clip on the timeline.
  6. Click Add text to caption a clip, then drag the text on the preview to place it.
  7. Set a clip's Speed for slow motion or fast forward, and Add music to play a track under the whole video.
  8. On each clip card, use ← / → to reorder or the trash icon to delete.
  9. Click Export and download the finished MP4.

Fast and lossless — why it's different

Because a single trim doesn't change the codec, that export copies the original stream instead of re-encoding it. The result is near-instant and lossless — the picture is exactly the same as your source, with no generation-loss blur. When you join multiple clips (or a source needs re-encoding), it uses hardware-acceleratedencoding via the browser's WebCodecs API to make the cuts frame-accurate, so it stays fast and clean. Everything happens on your device, so there is no upload wait and nothing to leak.

Good to know

  • The export is always an MP4 with the audio kept, so it plays on phones, editors, and social platforms.
  • Works in the latest Chrome, Edge, and Safari (and desktop Firefox 130+), which support the WebCodecs API.
  • Very large files are limited by your device's memory, since processing runs in the browser.

Need to shrink the file afterwards, or grab a still frame? Pair this with our image compressor and other browser tools — more video tools (convert and video-to-GIF) are on the way.

Frequently asked questions

Is this video editor free?

Yes — it's a completely free online video editor with no sign-up, no watermark, and no export limits. Trim as many videos as you like.

Is my video uploaded to a server?

No. Your video never leaves your device — it's loaded, previewed, and exported entirely in your browser. That means there's no upload wait and your footage stays private.

Can I cut out a part from the middle of the video?

Yes. Move the playhead to where you want to cut and press Split to break the clip in two, then delete the piece you don't want. The remaining clips are joined back together on export.

Can I join or reorder multiple clips?

Yes. Split a video into several clips, then use the arrows on each clip card to reorder them or delete the ones you don't need. Export stitches every clip together, in order, into one MP4.

Can I merge several different video files together?

Yes. Click Add video to bring in more files — each one becomes a clip you can trim, split, reorder, and delete alongside the others. Export joins them all into a single MP4, even when the videos have different resolutions, frame rates, or codecs.

What happens when I join videos of different sizes?

They're normalized to one output. The result is sized to your first clip; other clips are scaled to fit inside it (letterboxed with black bars if the aspect ratio differs), and all audio is resampled to a common format so it stays in sync. No source is stretched or distorted.

Can I add text or captions to the video?

Yes. Select a clip, click Add text, then type your caption and drag it anywhere on the preview. You can set the size, color, an optional background box, and exactly when it appears and disappears. The text is burned into the exported MP4, so it shows on every player.

Can I speed up or slow down a clip?

Yes. Select a clip and pick a speed from 0.25× (slow motion) up to 4× (fast forward). Each clip can have its own speed, and both the video and its audio are re-timed, so a sped-up clip is shorter in the final video.

Can I add background music?

Yes. Click Add music to bring in an audio file (MP3, WAV, M4A…). Set its volume, and optionally mute the clips' original sound so only the music plays. The track loops or trims to match your video's length and is mixed into the exported MP4.

Does trimming reduce the quality?

A single trim (no format or resolution change) copies the original video and audio without re-encoding, so it's lossless — bit-for-bit the same picture as your source. When you join two or more clips, the cuts are re-encoded so the joins are frame-accurate, using hardware-accelerated WebCodecs to stay fast and high quality.

Does the export keep the audio?

Yes. The original audio track is kept and stays in sync in the exported MP4.

Which browsers are supported?

The editor uses the WebCodecs API for fast, high-quality exports: latest Chrome, Edge, and Safari, plus desktop Firefox 130+. On an unsupported browser you'll see a notice instead of the editor.

Why is the export sometimes instant and sometimes slower?

A single-clip trim is a stream copy — near-instant and lossless. Joining multiple clips (or a source that needs re-encoding) uses hardware-accelerated encoding, which is still fast but takes longer than a plain copy.

What video formats can I use?

Most common formats your browser can play — MP4 (H.264/H.265), WebM (VP8/VP9/AV1), and MOV. The export is always MP4 so it plays everywhere.

Is there a file size limit?

There's no hard limit, but because everything runs in your browser's memory, very large files (multiple gigabytes) may be constrained by your device's available RAM.