Resize video
Change the resolution of MP4, MOV, WebM and MKV videos, for example to 1080p or 720p, and optionally make them square (1:1), vertical (9:16), widescreen (16:9) or 4:5 by cropping or adding black bars. The sound is copied unchanged.
Process locally
Files stay in this browser session. Closing or clearing releases them.
Choose files
MP4, MOV, WebM, MKV, up to 5
Drop files here, or
Adjust settings
Optional: Resolution, Shape, When the shape changes
Run
Processes in this browser; cancel at any time
Common tasks
About this tool
Resize a video in your browser, without uploading it: change its resolution to 1080p, 720p or another standard size, or change its shape for social media, such as square 1:1 for a feed, vertical 9:16 for Shorts, Reels and TikTok, widescreen 16:9 for YouTube or 4:5 for Instagram portrait posts.
When the shape changes, choose whether to crop the picture to fill the frame, keeping its centre, or to fit all of it inside and add black bars. Resolutions are named by the shorter side, so 720p makes a landscape video 1280 × 720 and a vertical one 720 × 1280. The picture is re-encoded, as H.264 for MP4, MOV and MKV and VP9 for WebM where the browser can, and the sound is copied unchanged.
How to use it
- Choose or drop up to 5 MP4, MOV, WebM or MKV videos, 80 MB in total.
- Pick a “Resolution”, or “Keep” to change only the shape.
- Pick a “Shape”, and under “When the shape changes” choose cropping or black bars.
- Select Run, check the result in the preview and download it.
Formats and limits
- Input
- MP4, MOV, WebM, MKV, up to 5 files
- Output
- Same format as the input
- Size limit
- 80 MB per file
- Settings
- Resolution (Keep, 2160p, 1440p, 1080p, 720p, 480p, 360p); Shape (Keep the original, Square 1:1, Vertical 9:16, Widescreen 16:9, Portrait 4:5); When the shape changes (Crop to fill, keep the centre, Fit inside, add black bars)
- Privacy
- Files stay in the current browser session. No file bytes are uploaded.
- Price
- Free, no sign-up
Common questions
How do I change a video from horizontal to vertical?
Choose “Vertical 9:16” under “Shape”. “Crop to fill” cuts off the left and right so the middle fills the screen; “Fit inside” keeps the whole picture with black bars above and below. 1080p then gives 1080 × 1920, the size Shorts, Reels and TikTok use.
What does 720p mean for a vertical video?
The resolutions here name the shorter side, so a vertical phone video at 720p becomes 720 × 1280 rather than being squeezed to 720 pixels tall.
Will resizing to a higher resolution make the video sharper?
No. Choosing a larger resolution than the video has enlarges it, which some sites ask for, but it adds no detail and makes the file bigger.
Is the sound kept?
Yes, the sound track is copied as it is. To remove it, use “Remove audio from video” on the result.
Why is resizing slower than trimming?
Every frame is decoded, scaled and encoded again. Each run may take at most 2 minutes, so for long videos choose a lower resolution or trim them first.
Workflows that use this tool
Related tools
Extract audio from video (MP4 to MP3)
Take the sound out of MP4, MOV, MKV or WebM video and convert it to MP3, M4A, OGG, WebM or WAV, or keep the track unchanged in its own container, optionally trimmed. Files are not uploaded.
Convert video format
Convert between MP4, WebM, MKV and MOV; MP4 and MOV get H.264 video and AAC sound so any player opens them, and other formats copy streams when they can. Scale down, remove the sound or trim at the same time. Encoding uses the browser.
Trim video
Cut a clip out of an MP4, MOV, WebM or MKV video by start and end time. By default the video and sound are copied without re-encoding, so it is fast and the quality is unchanged; exact cutting re-encodes the video to start on the exact frame.
Compress video
Make MP4, MOV, WebM and MKV videos smaller by quality level, target file size or bitrate, with an optional resolution limit. Encodes H.264 (MP4), VP9 (WebM) or AV1 (MP4) with the browser’s own encoder.
Remove audio from video
Mute MP4, MOV, WebM and MKV videos by removing the audio track. The picture is copied without re-encoding, so its quality, resolution and rotation stay exactly the same.
Video to GIF
Convert part of an MP4, MOV, WebM or MKV video into an animated GIF, with start and end times, width, frame rate and loop count. A GIF holds up to 600 frames, such as 60 seconds at 10 fps.