Resize a video to 1080x1920, the vertical delivery frame for Reels, Shorts, TikTok, and Stories.
Coming from 1920x1080
This is the most destructive of the common resizes. The tallest 9:16 rectangle that fits inside a 16:9 frame is 608 pixels wide, so crop to fill keeps 32% of the original width and cuts 656 pixels from each side.
That is the right call when one subject sits near the middle: a talking head, a single product, a phone screen recording. It is the wrong call for a wide shot, a two-person interview, or anything where the edges carry the composition.
The kept area is always centered. To choose which 608 columns survive, crop the video first, then resize the result.
Keeping the sides instead
When the edges carry the composition, padding beats cutting. That is the video cropper with Frame mode set to Fit with bars: all 1920 columns survive as a 1080x608 band across the middle, with 656 pixels of background above and below it, filled with a blurred copy of the frame, black, white, or a color.
Safe areas
Platform interface sits over the top and bottom of a vertical clip: captions, the username, the action rail. Keep anything that must stay legible inside the middle 60% of the height, roughly 384 to 1536 pixels on a 1080x1920 export.
When it is already vertical
Most phones record 1080x1920 upright. Resizing such a file to 1080x1920 changes nothing about the framing, though it still re-encodes. If the file is already the right size and you only need it smaller, compress it instead.