Resize video online
Resize a video online for YouTube, TikTok, Instagram and Reels easily. Try the tool right now. 100% local in-browser processing, nothing ever uploaded to
Drop your video here
MP4, WebM, AVI, MOV supported
Supported formats
How it works
Step 1
Load your video
Step 2
Select dimensions or ratio (16:9, 9:16, 1:1.)
Step 3
Download resized video
Common mistakes
- Uploading a video file too large for the browser (keep it under 2 GB).
- Closing the tab before processing finishes: the conversion stops.
- Using an exotic input format (prefer MP4, WebM, MOV, AVI).
- Picking a bitrate so low that quality drops noticeably.
Pro tips
- Pick H.264 (MP4) for the widest compatibility.
- For the web, use WebM (VP9/AV1): smaller file at the same quality.
- Keep the original: processing is local but the download is final.
- On mobile, plug in the charger for long videos.
Privacy guaranteed
local resizing. Your video never leaves your device.
Resize for Instagram Reels — free online, no signup required
Instagram Reels require vertical 9:16 format (1080x1920). Adapt your landscape videos to the ideal format. Resizing changes resolution (width × height in pixels), adjusts the aspect ratio (16:9, 9:16, 1:1, 4:3) and optimizes the video for portrait, landscape and square formats used on YouTube, Instagram Reels or TikTok.
Also discover our tool to crop video online.
Technical details
Resize your videos to 4K, 1080p, 720p or 480p with precise scaling: upscale for more definition or downscale to lighten the file.
Why choose our online video resizer
Our online video resizer stands out with 100% local processing via FFmpeg.wasm directly in your Chrome, Firefox, Safari or Edge browser — no server upload, no queue, no arbitrary size limit. You get a fast, free, no-signup, watermark-free tool compatible with all your MP4, MOV, AVI, MKV, WebM, FLV, WMV, M4V, 3GP files and more. Perfect for YouTubers, TikTokers, Instagram Reels creators, Premiere Pro editors, DaVinci Resolve, CapCut, Final Cut users, marketing pros, e-learning trainers and individuals who want to resize video online without installing heavy software like HandBrake, Adobe Media Encoder or VLC.
Cross-device compatibility — PC, Mac, iPhone, Android
Our video resizer works on Windows 10, Windows 11, macOS Ventura, Sonoma, Sequoia, Linux Ubuntu, Debian, Fedora, as well as iOS 16+ (iPhone, iPad), iPadOS, Android 10+ (Samsung Galaxy, Google Pixel, Xiaomi, OnePlus) and even Chrome OS on Chromebook. No native app, no APK, no .exe to download: just open the page in your favorite browser and start processing your videos. Compatible with videos from smartphones (4K HDR, slow-motion), GoPro cameras, DJI drones, OBS screen captures, After Effects exports, Loom screencasts and files downloaded from YouTube, Vimeo, TikTok, Twitch or Twitter/X.
Privacy, GDPR compliance and video security
Unlike competing services (Clideo, Kapwing, Veed.io, FlexClip, Online-Convert, Convertio, CloudConvert, FreeConvert, EZGif, Zamzar) that upload your files to remote servers in the US or Asia, our tool processes your entire video in your browser's RAM. Not a single byte is sent over the Internet, ensuring full GDPR, CCPA, LGPD and HIPAA compliance. Perfect for confidential business documents, medical, legal, educational videos, copyrighted content and any personal file you do not want to entrust to any third party.
Discover all our video tools
Compress, convert, cut, resize and edit your videos in a few clicks.
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Guides and tutorials
Frequently asked questions
What dimensions for Instagram?
Stories and Reels: 1080x1920 (9:16). Square feed: 1080x1080 (1:1). Landscape feed: 1080x566 (1.91:1).