Resize a video for TikTok, Instagram or YouTube
Pick a platform preset and choose whether the video should fit inside the frame or fill it. Vidmini resizes the video on your own device, without uploading it.
How it works
- 1
Choose or drop the video you want to resize (MP4, MOV, WebM or MKV).
- 2
Pick a size, such as "TikTok · Reels · Shorts" 1080×1920 or "YouTube 1080p" 1920×1080, then choose "Fit (add borders)" or "Fill (crop edges)".
- 3
Click Resize Video and download the result. The file never leaves your device.
Presets for every platform
Each platform prefers a particular frame. Vertical feeds such as TikTok, Instagram Reels and YouTube Shorts use 1080×1920 (9:16). Instagram posts look best at 1080×1350 (4:5 portrait) or 1080×1080 (square). YouTube and most TVs and laptops use 1920×1080 (16:9). Vidmini offers all of these as presets, plus 720p and 480p when you just want a lighter, smaller video.
Using the exact size a platform expects avoids surprises: the app does not have to scale or crop your video itself, and you decide what stays in the frame instead of an automatic crop cutting off a face or a caption.
Fit or fill: borders or cropped edges
When your video's shape differs from the target, there are two ways to make it fit. "Fit (add borders)" scales the whole picture down until it fits inside the frame and adds borders to fill the gaps. Nothing is cut off; a landscape clip placed in a 9:16 frame gets bars above and below.
"Fill (crop edges)" scales the picture up until the frame is completely covered and crops whatever spills over the edges. There are no borders, but the sides (or the top and bottom) are lost. Choose fit when everything in the shot matters, such as a slide or a screen recording, and fill when the subject is in the middle and you want a full-screen look.
Resize, crop or compress?
These three tools are often confused. Resize changes the pixel dimensions of the whole video to a target size, adding borders or trimming edges as needed. Crop Video keeps the original pixels and cuts out a region in a chosen aspect ratio (9:16, 1:1, 4:5, 16:9 or 4:3), with a slider to choose which part to keep. Compress Video keeps the picture as it is but reduces the file size in megabytes.
If your goal is a smaller file to send, compression is usually the better choice; resizing to 720p or 480p also reduces size, but you pick the dimensions rather than the megabytes. If you need a vertical video from a landscape one and want to control exactly which part is kept, use Crop Video. You can chain the tools with "Continue with this file" without selecting the file again.
On your device, with no upload
Resizing changes every frame, so the video is re-encoded using your browser's WebCodecs API and your device's hardware encoder when available. The work happens entirely in your browser: nothing is uploaded, no account is needed and no watermark is added. There is no size limit set by us; desktop browsers handle multi-gigabyte files, while phones depend on free memory and storage.
Frequently asked questions
What size should a TikTok or Reels video be?
1080×1920 pixels, a vertical 9:16 frame. The "TikTok · Reels · Shorts" preset produces exactly that. Use "Fill (crop edges)" for a full-screen look or "Fit (add borders)" to keep the whole picture with borders.
What is the difference between fit and fill?
Fit keeps the entire picture and adds borders where the shapes do not match. Fill covers the whole frame and crops the parts that stick out. Neither stretches or distorts the image.
Can I make a video smaller in file size by resizing it?
Yes, lowering the resolution to 720p or 480p usually makes the file noticeably smaller. If you need a specific size in MB, Compress Video lets you set that target directly.
Does resizing reduce quality?
The video is re-encoded, which involves a small generation loss. Scaling down to a smaller size looks sharp; scaling a small video up to a larger size cannot add detail that was not there.
Which formats can I resize?
MP4, MOV (including iPhone videos), M4V, WebM and MKV, with codecs your browser can decode, such as H.264, HEVC, VP9 and AV1. AVI, WMV and FLV files also work: they are first converted on your device by a built-in fallback, which is slower and downloads a 32 MB converter the first time.
Is my video uploaded to a server?
No. Resizing happens in your own browser, and the page's Content Security Policy only allows it to contact vidmini.com for its own code. No tracking cookies are used.