Video Converter for Instagram, TikTok & YouTube

Each social platform has a preferred shape: tall 9:16 for Reels, TikTok, Shorts and Stories, 4:5 for the Instagram and Facebook feed, square 1:1, and wide 16:9 for YouTube and X. This converter turns any video into one of those formats at 1080p, as an H.264 + AAC MP4 that every app accepts. A video of a different shape can sit on a blurred copy of itself, between bars, or be cropped to fill the frame, and you can also trim it, cap the frame rate, remove the sound or aim for a file size.

How to use this tool

1. Choose the target format, for example 1080 × 1920 for Reels and TikTok.
2. Choose blurred background, bars or crop for videos of a different shape.
3. Optionally set a frame rate, a maximum length or a target file size.
4. Choose one or more videos, then download the results.

Formula

Fit inside: scale = min(W ÷ w, H ÷ h) · Fill and crop: scale = max(W ÷ w, H ÷ h) · Bitrate for a target size = MB × 8,000 ÷ seconds × 0.96 − 128 kbps

w × h is the picture as players show it (rotation applied, non-square pixels corrected) and W × H the chosen format. With “fit inside” the whole picture stays visible and the empty space is filled with bars or with a blurred, enlarged copy of the video; with “crop” the frame is filled and the edges are cut off. Sizes are rounded to even numbers for H.264. In target-size mode 4% is reserved for the file’s structure and 128 kbps for the sound. The video engine (ffmpeg compiled to WebAssembly, about 30 MB) loads the first time you use it.

Example

A 1920 × 1080 landscape clip converted to 1080 × 1920 with the blurred background is scaled to 1080 × 608 and centred, with 656 pixels of blurred video above and below. A 30-second clip with a 10 MB target gets 10 × 8,000 ÷ 30 × 0.96 − 128 = 2,432 kbps for the picture.