How to Turn Any Video into a Reel or Short: Crop to 9:16, Trim and Compress

Instagram Reels, YouTube Shorts and WhatsApp Status are all built for a phone held upright: a tall 9:16 frame. If your clip was filmed sideways, or it’s a screen recording or a camera video in 16:9, uploading it as it is leaves thick black bars or a tiny picture. Here’s how to turn it into a proper vertical video in three steps, without installing an editor or uploading your footage to a website.

What size should a Reel be?

9:16 is the shape; the ideal size is 1080 × 1920 pixels, which is what Instagram recommends for Reels. The apps accept smaller vertical videos too and scale them up for viewers, so a sharp 720 × 1280 or even 608 × 1080 clip still fills the screen.

When you crop a 16:9 landscape video to 9:16, you keep a tall strip from it. From a 1920 × 1080 video, that strip is 608 × 1080: about a third of the width. That’s why framing matters: whatever is outside the strip is gone.

Step 1: Crop to 9:16

1. Open Crop Video for Reels. The 9:16 box is already selected.
2. Drop in your video.
3. Drag the box over your subject. Use Preview at to scrub through the video and check the subject stays inside the box later on. The box stays in the same place for the whole video.
4. Leave Output size on “Same as crop” and click Crop video.

The result is an MP4 with H.264 video, the format every app accepts, with the original sound kept. The tool never enlarges the video, because scaling up adds file size without adding detail.

The same Crop & Resize Video tool also does 1:1 squares and 4:5 portrait posts for the feed, and 16:9 if you’re going the other way, from a vertical clip to a YouTube-style frame.

Step 2: Keep only the best part

Short-form video rewards getting to the point. Open Trim Video, play the clip, and set the start and end with Set to playhead:

• Fast copies the video without re-encoding, so it takes a second and keeps full quality. Players start at your chosen time, though the file also holds a few seconds before it, back to the previous key frame.
• Exact re-encodes the clip so the file holds only what you chose. Use it if an app shows extra seconds at the start.

Trimming before cropping saves time, because the crop then only has to re-encode the part you keep.

Step 3: Make sure it uploads quickly

Phone videos are large, and some upload screens are slow on mobile data. If the file is big, run it through the Video Compressor with a target such as 25 MB. A short vertical clip still looks good at that size, and it uploads in a fraction of the time.

Other quick fixes

• Video is sideways or upside down? Rotate it first. MP4 and MOV files rotate instantly without re-encoding.
• Front-camera video with backwards text? Flip it left to right.
• Need a cover image? Pause on the best moment in the Video Thumbnail Maker and save that frame as a JPG.
• Want a looping preview for a website or chat? Turn a few seconds into a GIF.

All of these run in your browser. Your clips aren’t uploaded, there’s no watermark, and you don’t need an account.