Video Resizer — Resize Videos Online Free

Free, private, serverless video resizer. Resize videos to any resolution with presets for 4K, 1080p, 720p, Instagram, TikTok — 100% client-side.

🔒 100% Private
Completely Free
🌐 Runs in Browser
📦 Export Ready

Video Resizer — Resize Videos Online Free

Tool Workspace

Ready

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  1. Upload: Drag and drop or click to upload a video.
  2. Choose Size: Pick a preset (4K, 1080p, 720p, 480p, 360p, Instagram, TikTok, Twitter) or enter custom dimensions.
  3. Resize: Click Resize — the video is re-encoded at the new resolution using H.264.
  4. Download: Save the resized video.

Video Resizer — Change Video Resolution in Your Browser

Our Video Resizer uses FFmpeg.wasm to resize videos to any resolution — with 8 built-in presets for popular platforms and custom dimension support. All processing happens 100% in your browser.

Resolution Presets

  • 4K (3840×2160): Ultra HD for high-end displays
  • 1080p (1920×1080): Full HD — standard for YouTube and most platforms
  • 720p (1280×720): HD — good balance of quality and file size
  • 480p (854×480): Standard definition for smaller screens
  • 360p (640×360): Low resolution for minimal file sizes
  • Instagram (1080×1080): Square format for Instagram feed
  • TikTok (1080×1920): Vertical 9:16 format
  • Twitter (1280×720): Landscape format optimized for Twitter

How It Works

The tool uses FFmpeg's scale filter to resize the video, then re-encodes with H.264 (CRF 23) for high quality output. Audio is preserved with AAC encoding at 128kbps. The output includes the faststart flag for optimized web playback.

Common Use Cases

  • Social media optimization: Resize for Instagram, TikTok, Twitter, YouTube
  • File size reduction: Downscale large 4K videos to 1080p or 720p
  • Upscaling: Scale up lower resolution videos (quality depends on source)
  • Aspect ratio changes: Convert landscape to square or portrait

Privacy

All processing happens locally in your browser using WebAssembly. No video data is transmitted to any server.

Frequently Asked Questions

Is my data safe?

Yes. All processing happens in your browser using FFmpeg.wasm. No video is uploaded.

What presets are available?

4K (3840×2160), 1080p, 720p, 480p, 360p, Instagram square (1080×1080), TikTok vertical (1080×1920), and Twitter (1280×720).

Can I use custom dimensions?

Yes. Enter any width and height in pixels. Dimensions are automatically adjusted to even numbers for H.264 compatibility.