What does Vid-mix Editor do?
Import video and audio, place clips on a timeline, trim and frame each video into a social format (9:16, 16:9, and more), then render one H.264 MP4 in your browser.
Interactive calculator loads when JavaScript is enabled. All calculations stay on your device.
Usage
- Cut two moments from one take and stitch them for Reels or TikTok.
- Frame landscape footage into 9:16 with drag-to-reposition framing.
- Lay music or voiceover on the audio track and render one MP4.
- Letterbox a vertical clip into 16:9 for YouTube.
- Reorder clips on the timeline before you render.
- Keep drafts private — encode locally before uploading anywhere.
Knowledge
Output format sets the canvas (Shorts, Reels, YouTube 16:9, feed 4:5, and more). Framing is how each video clip fits that canvas — crop, letterbox, or stretch — with pan when cropping.
Use Add another cut from this video to place multiple segments from the same file with different trims.
Limits
- Library: up to 5 videos, 5 images, and 5 audio files (separate caps).
- Timeline: up to 8 video clips, 8 images, and 5 audio clips per audio track.
- Each video under 150 MB / 3 minutes; combined library under 300 MB.
- Images and text are burned into the MP4. Mute / volume on video and audio clips are applied in the export; timeline audio mixes with unmuted video soundtracks.
FAQs
Is my media uploaded?
No. Probing, trimming, framing, and encoding run in your browser (WebCodecs when available, with an on-device fallback). Files never leave this device.
What render options can I choose?
Before encoding, pick resolution scale (0.5× draft, 1× full, or 2×), quality (Draft / Good / High), and frame rate. The dialog estimates file size and shows a live preview while rendering. Save the finished MP4 to your device when it is ready.
Can I use parts of the same video more than once?
Yes. Select a video clip and choose “Add another cut from this video” to place a second segment on the timeline with its own trim and framing.
What about audio?
Drop MP3, M4A, or WAV onto the timeline’s audio tracks. Mute and volume on video and audio clips are applied in the render. Timeline audio mixes with unmuted video soundtracks.
Why are there size and length limits?
Browser memory is limited. Each video must be under 150 MB and 3 minutes. You can keep up to 5 videos, 5 images, and 5 audio files in the library (300 MB combined). Timeline length follows the selected output format.
Which formats work best?
MP4 (H.264) and WebM for video; MP3 or M4A for audio. If preview fails, re-export as MP4 / MP3.