A Reels video resizer for Instagram and Facebook
Reels are built for a phone held upright. A landscape clip posted as a Reel is shrunk into a band across the middle of the screen, and a careless crop can cut a speaker in half. This Reels video resizer turns any video into a 9:16 Reel — 1080 × 1920 by default — with a blurred copy of the footage behind it, a colour fill, or a crop that pans to follow the action. A preview-only overlay shows the safe zone Meta publishes, so captions and faces don’t end up under the buttons.
There is nothing to install and no upload. Mediabunny, an open-source media library under the MPL-2.0 licence, reads your file in the browser; each frame is redrawn on a canvas and your browser’s WebCodecs encoder saves an H.264 MP4 with AAC sound — the codecs Meta lists for Reels ads.
How to resize a video for Reels
- Drop your video on the upload area and check its length, resolution and frame rate in the summary.
- Choose “Instagram Reel 9:16 · 1080 × 1920”, the Facebook Reel option, or the 1440 × 2560 Reels-ad size.
- Pick the fill — Blurred video, Colour or Nothing — crop — and adjust blur, darkening or Zoom while you watch the preview.
- Keep faces and text inside the dashed safe-zone box. To follow a moving subject, turn on keyframes and drag the preview at a few moments.
- Press “Make Reel”, play the result to check it and press “Download MP4”. Then post it from the Instagram or Facebook app.
Reels Video Resizer features
Meta’s safe zone on the preview
The overlay leaves 14% at the top, 35% at the bottom and 6% at each side, as Meta’s Ads Guide advises for Reels. It is never burned into the video.
Instagram length checks
Clips over 3 minutes get a reach warning, and anything over Instagram’s 20-minute Reels length can be cut automatically.
Blurred, colour or crop fill
Keep a whole landscape shot on a soft background, use brand colours, or fill the screen with a crop.
Moving crop with keyframes
The 9:16 window glides between the positions you set, like a camera operator following the action.
Ad-ready option
A 1440 × 2560 preset with the 15-minute and 4 GB limits from Meta’s Reels ad specs.
Reels specs as of 2026
Meta updates these figures from time to time; the sources are listed at the end of this page.
| Setting | Instagram Reels | Facebook Reels |
|---|---|---|
| Shape | 1.91:1 to 9:16 (9:16 fills the screen) | 9:16 fills the screen |
| Quality | At least 720 px and 30 fps | — |
| Length | Record and edit up to 20 minutes; over 3 minutes isn’t recommended to new audiences | No length limit since June 2025 |
| Safe zone (ads) | 14% top, 35% bottom, 6% sides | Same Meta guidance |
| Ads | 1440 × 2560 recommended, up to 15 minutes and 4 GB, H.264 + AAC 128 kbps or more | — |
Blurred background or crop for Reels?
If the original was filmed wide — a presentation, a match, a cooking bench — keep everything with “Blurred video” and raise Zoom to around 130–150% so the picture takes up more of the screen. If one person is talking to camera, crop instead: the Reel fills the whole screen and keyframes keep them centred as they move.
Either way, avoid putting subtitles in the bottom third. On Reels the caption, audio label and buttons sit there, which is exactly why Meta’s safe zone keeps the bottom 35% clear.
Before you post
- Long recordings convert faster if you trim them first with the video cutter.
- For feed posts in 4:5 or 1:1, use the Instagram video resizer; for a Reel cover image, the Instagram image resizer.
- The same clip for other apps: YouTube Shorts or TikTok.
Sources (checked October 2026)
- Instagram Help — Record a reel on Instagram (up to 20 minutes; over 3 minutes not recommended to new audiences)
- Instagram Help — reel aspect ratio and quality (1.91:1 to 9:16, 30 fps, 720 px)
- Meta Ads Guide — Instagram Reels video ads (1440 × 2560, H.264, AAC, 4 GB, safe zone)
- Meta Newsroom — Making it easier to create videos on Facebook (17 June 2025)
Reels Video Resizer FAQ
What size should a Reel be?
9:16, usually 1080 × 1920 pixels. Instagram accepts shapes from 1.91:1 to 9:16 and asks for at least 720 px and 30 fps, but only 9:16 fills the whole screen. This Reels video resizer makes 1080 × 1920 by default.
How long can an Instagram Reel be?
Instagram lets you record and edit reels up to 20 minutes, but says reels longer than 3 minutes aren’t recommended to people who don’t follow you. The tool warns above 3 minutes and can cut at 20.
Do Facebook Reels have a time limit?
Meta announced in June 2025 that all videos on Facebook are shared as reels, with no length or format restrictions.
Where should text go on a Reel?
Inside the safe zone: keep roughly the top 14%, the bottom 35% and 6% on each side clear, as Meta advises for Reels ads. Turn on “Show safe zones” to see that area on the preview.
Can I post a landscape video as a Reel without cropping it?
Yes. Choose “Blurred video” or “Colour”; the full landscape picture stays visible and the rest of the 9:16 frame is filled.
Is my video uploaded?
No. The Reel is made in your browser and saved straight to your device; you upload it to Instagram or Facebook yourself.