Resize Video – Change Video Resolution & Aspect Ratio
Resize video to a standard resolution such as 1080p or 720p, or to the exact frame of TikTok, Reels, Shorts, Stories or YouTube. When the shape changes, you choose between a blurred background, bars, cropping or stretching, so nobody’s face gets squashed. A whole batch resizes in one go, in your browser, with nothing uploaded.
- Runs on your device
- WebCodecs · GPU
- FFmpeg
- Works offline
Updated
Drop your videos here
How to resize a video
Step 1: Drop one or more videos on the box above.
Step 2: Pick a Size: 1080p, 720p, 480p or 4K to keep the shape, a social preset, or Custom size for any width × height.
Step 3: If the new shape differs from your video, choose Fit (add bars) with blurred, black, white or coloured bars, Fill (crop) or Stretch.
Step 4: Press Resize and download each video, or all of them as a ZIP.
Good to know
Settings explained
- Quality
- Only used when a stream has to be re-encoded. Compatible streams are copied with no quality loss.
- Faster: Smaller file, quickest export
- Balanced: Good quality at a sensible size
- Best quality: Largest file, slowest export
Formats
Batch-friendly: add many files and they are processed one after another — if one fails, the rest still finish.
How it runs
- Hardware video engine
- Video is decoded and encoded by your device’s media hardware through WebCodecs — usually several times faster than real time.
- FFmpeg (when needed)
- Older formats and a few filters use FFmpeg compiled to WebAssembly. It downloads once (about 31 MB) the first time it is needed and is cached for offline use.
| Use | Shape | Pixels |
|---|---|---|
| TikTok | 9:16 | 1080 × 1920 |
| Instagram Reels | 9:16 | 1080 × 1920 |
| YouTube Shorts | 9:16 | 1080 × 1920 |
| Instagram / Facebook Story | 9:16 | 1080 × 1920 |
| Instagram feed (portrait) | 4:5 | 1080 × 1350 |
| Instagram feed (square) | 1:1 | 1080 × 1080 |
| YouTube (1080p) | 16:9 | 1920 × 1080 |
| X / Twitter | 16:9 | 1280 × 720 |
Checked 11 October 2026. Platforms change their limits — check the official help pages if a number looks different.
Fit, Fill or Stretch: what happens when the shape changes
A 16:9 video does not fit a 9:16 frame, so something has to give. Fit keeps the whole picture and fills the gap with bars. Fill fills the frame and cuts off the sides. Stretch fills it by distorting the picture. The numbers show a 1920×1080 video going into a vertical frame.
| Fit option | What you get | Good for |
|---|---|---|
| Fit (add bars) with blurred bars (default) | The full picture at 1080×608 in the middle, a blurred copy of it above and below | Talking heads, gameplay, anything where the edges matter |
| Fit with black, white or a colour | The same 1080×608 picture with solid bars of 656 pixels top and bottom | Clean, branded or presentation-style posts |
| Fill (crop) | The centre 32% of the width, scaled to fill the frame | Subjects in the middle of the shot |
| Stretch | The whole picture squeezed to fit, people look thin | Rarely; only when the source shape was wrong to begin with |
How to change video resolution and keep the shape
The 1080p, 720p, 480p and 4K presets set the short side of the video to that number and scale the other side to match, so a landscape and a vertical clip both come out right. Nothing is cropped and no bars are added. If a video already has the size you pick, it is copied without re-encoding.
| Preset | From 3840×2160 (landscape 4K) | From 1920×1080 (landscape HD) | From 1080×1920 (vertical phone) |
|---|---|---|---|
| 1080p | 1920×1080 | Same size, copied | Same size, copied |
| 720p | 1280×720 | 1280×720 | 720×1280 |
| 480p | 854×480 | 854×480 | 480×854 |
| 4K | Same size, copied | 3840×2160 (enlarged) | 2160×3840 (enlarged) |
Resize video for Instagram, TikTok and YouTube Shorts
TikTok, Instagram Reels, YouTube Shorts and Stories all use a vertical 9:16 frame of 1080×1920 pixels. Instagram feed posts are 1080×1350 (4:5) or 1080×1080 (square), regular YouTube videos 1920×1080, and X (Twitter) 1280×720. Each one is a preset in the Size list, so you do not have to type the numbers.
To post a landscape clip vertically without cutting anyone out, choose the Reels or TikTok preset and leave Fit (add bars) on blurred bars. If the subject sits in the centre and you would rather fill the screen, pick Fill (crop), or move the crop window yourself with the horizontal to vertical video converter.
Does resizing a video reduce quality?
Making a video smaller (4K to 1080p, 1080p to 720p) keeps it looking sharp on the screens it is meant for, and the file usually shrinks a lot. The video is re-encoded once, as H.264 for MP4, MOV and MKV or VP9 for WebM, at the Quality you choose under Advanced settings; the sound is copied unchanged.
Making it larger never adds detail: a 720p clip resized to 1080p only looks as sharp as the 720p original. Do it only when a platform insists on a minimum resolution. If your real goal is a smaller file in megabytes rather than fewer pixels, the video compressor is the better tool.
Resize a video on iPhone, Android, Windows or Mac
This video resizer works the same way in Safari, Chrome, Edge and Firefox. A few built-in apps can also export at a lower resolution.
iPhone and iPad
The Photos app cannot change resolution. Open this page in Safari, pick clips from Photo Library and choose a preset; save the results to Files or Photos.
Android
In Chrome, tap the drop zone and select several clips at once from your gallery. Resized videos are saved to Downloads.
Windows
Clipchamp exports at fixed resolutions such as 720p or 1080p, one project at a time. For a folder of clips, drag them all into the browser here.
Mac
QuickTime Player’s File → Export As offers fixed resolutions for one file. Here you can resize a batch to social sizes with a blurred background.
Tips & troubleshooting
Need to cut part of the frame away rather than fit it? Crop the video with a free-form box or a fixed ratio.
For a smaller file, pair resizing with compression: 720p has 44% of the pixels of 1080p, and the video compressor can then hit an exact MB target.
Changing the frame rate or codec as well? The video encoder sets resolution, frame rate and bitrate in one pass.
Resizing a mix of portrait and landscape clips? The keep-shape presets scale each file by its short side, so one batch handles both orientations.
Resize Video FAQ
What size should a video be for Instagram Reels?
Reels use a vertical 9:16 frame of 1080×1920 pixels. Choose the Instagram Reels preset; a landscape clip gets blurred bars by default, or switch to Fill (crop) to fill the screen.
What is the video size for TikTok?
TikTok uses 1080×1920 pixels, the same 9:16 frame as Reels, Shorts and Stories. Pick the TikTok preset and the video is scaled to exactly that size.
Can you resize a video without cropping?
Yes. Keep-shape presets (1080p, 720p, 480p, 4K) never crop. For a different shape, choose Fit (add bars): the whole picture stays visible and the empty space is filled with a blurred copy of the video or a solid colour.
How do I resize a video without losing quality?
Resize down, not up, and set Quality to Best under Advanced settings for footage you will edit again. A video that already matches the chosen size is copied as it is, with no re-encode.
How do I change the aspect ratio of a video?
Choose a preset or a custom size with the new shape, then decide how to fill it: bars (blurred or solid), a crop, or a stretch. To cut the frame to a ratio instead, use Crop Video.
Will resizing to 4K make my video sharper?
No. Enlarging cannot recreate detail that was never recorded; it only makes the file bigger. It helps only when a site requires a minimum resolution.
Is your video uploaded anywhere?
No. Your video is processed by your own browser on your own device. There is no server that receives files, so nothing is uploaded, stored or shared. You can even switch to airplane mode once the page has loaded.