Resize video for social media
Resize video to 16:9 for YouTube, 9:16 for TikTok/Reels, or 1:1 for Instagram. Instant browser-based scaling with pad. Processed 100% on your device, no upload.
Drop a video to resize
Choose 16:9, 9:16, or 1:1 for social platforms
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💡 Expert insights & guides
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How to resize video for YouTube, TikTok, and Instagram
Upload your video and choose a target aspect ratio: 16:9 for YouTube landscape, 9:16 for TikTok and Instagram Reels, or 1:1 for Instagram feed posts.
FFmpeg WASM scales and pads your video to the correct frame size while preserving the original content — black bars fill unused space when needed.
Processed 100% on your device — no files are uploaded to any server. Watch the progress bar during encoding and download your social-ready MP4 instantly.
Why choose SnapKit? Our tools are 100% Private, No Server Upload, Instant Browser-Based, with No File Size Limit — plus free ringtone and video makers. Whether you merge PDFs, convert HEIC photos, or trim MP4 clips, your files stay on your device with zero cloud storage.
Why choose SnapKit?
Every tool is built around four promises: privacy, speed, freedom, and accessibility. No cloud pipeline — just your browser and your files.
100% Private — No Server Upload
Files are processed on your device with client-side WebAssembly and Canvas. No bytes are sent to our servers.
Instant Browser-Based speed
Skip slow uploads and downloads. Your CPU and GPU do the work locally for near-instant results.
No File Size Limit — Free forever
No registration walls, no watermarks, and no arbitrary caps. Use ringtone, video, PDF, and image tools freely.
Works on every device
iPhone, Android, Windows, and Mac browsers are all supported with the same private, instant experience.
Frequently asked questions
How do I resize video to 9:16 for TikTok in the browser?
Upload your clip, select 9:16 — TikTok / Reels, and click Resize video. FFmpeg WASM pads and scales locally. Processed 100% on your device — no files are uploaded to any server.
Can I make a YouTube 16:9 video without uploading?
Yes. Choose the 16:9 — YouTube preset to export a 1920×1080 padded frame. All processing is 100% secure and browser-based on your device.
Is resizing video online safe?
Yes. Your video never leaves your browser. No server upload, no cloud storage, and no account required — ideal for drafts and client previews.
Is my data safe with this tool?
Yes. All processing runs 100% on your device using client-side WebAssembly, Canvas API, and browser APIs. No bytes from your files are transmitted to our servers — zero server upload, absolute privacy.
Why is the processing speed so fast?
Because your file never leaves your browser. SnapKit uses WebAssembly and Canvas to harness your device CPU and GPU directly, skipping slow network upload and download steps.