Resize a video for any platform
Pick the platform, pick crop or pad, download. A landscape recording becomes a full-screen 9:16 Reel or a 1:1 feed post without opening an editor. Resizing runs locally in your browser; nothing is uploaded.
Runs in your browser with ffmpeg. The file is never uploaded.
About the video resizer
Every platform has its own frame and punishes the wrong one: a 16:9 clip posted to Reels or TikTok shows as a thin strip with black bars, a 9:16 clip on YouTube gets pillarboxed, and Instagram's feed crops anything taller than 4:5. Resizing properly means two things: scaling to the target resolution the platform actually serves, and deciding what to do with the leftover shape. This tool has presets for the ones that matter: 1080x1920 for Reels, TikTok, Shorts and Stories; 1080x1080 for square feed posts; 1080x1350 for the portrait feed format Instagram favours; 1920x1080 for YouTube and presentations; plus a custom width for anything else. For the shape, crop fills the frame by scaling up and cutting the edges, centred, which is right for talking heads and product shots; pad scales the whole video down to fit and fills the rest with black bars, which is right when nothing can be lost, like a screen recording with UI at the edges. Output is H.264 MP4 at a quality that survives the platform's own re-compression, with even dimensions and a fast-start index. Because the work happens on your device with ffmpeg in WebAssembly, a 4K source resizes without an upload.
How it works
Drop your video
MP4, MOV, WebM or MKV, up to 500MB. It is processed in your browser with ffmpeg, nothing is uploaded anywhere.
Pick the settings
Times, quality, size or speed depending on the tool. A progress bar shows how far along the export is.
Download
The result saves to your device. Free, no watermark, no signup.
Tips for best results
Things that meaningfully improve the output.
Crop for people, pad for screens
Faces and products survive a centred crop. Slides and app recordings have important content at the edges, so pad them instead.
Shoot with the crop in mind
If you know a landscape clip will become a Reel, keep the subject in the centre third while recording. The crop keeps the middle.
4:5 beats 1:1 on the Instagram feed
Portrait 1080x1350 takes up more screen than a square, which is why most brands post it. Square is for grids that must look uniform.
One export per platform
Resize the original for each destination rather than resizing a resized file. Every re-encode costs a little.
Need more than video resizer?
renza turns photos into video with Kling, Veo and Seedance, and upscales footage to 4K. Free credits at signup, no credit card.
Create free account →Frequently asked questions
What sizes do Instagram, TikTok and YouTube want?
Reels, TikTok, Shorts and Stories: 1080x1920 (9:16). Instagram feed: 1080x1080 (1:1) or 1080x1350 (4:5). YouTube: 1920x1080 (16:9). All are presets here.
Will the video be stretched?
Never. Crop and pad both keep the original proportions; crop trims the edges and pad adds bars. Stretching is not offered because it always looks wrong.
Is my video uploaded?
No. Resizing runs in your browser with ffmpeg compiled to WebAssembly. The file stays on your device.
Does it upscale a small video?
The presets scale to the target size in either direction. Upscaling a 480p clip to 1080p will look soft; there is no way around that without an AI upscaler.
Can I pick where the crop lands?
The crop is centred, which suits most footage. Off-centre subjects are better handled by trimming the clip first or shooting with the centre in mind.