Video Aspect Ratio Converter

Step-by-Step Guide

Step 1: Upload your video. Drag and drop a video file or click to browse. Supports MP4, MOV, WebM, and most common formats up to 500MB.

Step 2: Select target aspect ratio. Choose from presets like TikTok/Reels (9:16), YouTube (16:9), or Instagram (1:1, 4:5). Or set custom dimensions for any resolution you need.

Step 3: Choose conversion mode. "Crop" fills the frame by cropping edges (choose top/center/bottom focus). "Letterbox" adds colored bars to fit the video without cropping.

Step 4: Convert and download. Click "Convert Aspect Ratio" and wait for processing. Download your resized video when complete.

9:16 - TikTok, Instagram Reels, YouTube Shorts. Vertical video optimized for mobile phones. The most popular format for short-form content that fills the phone screen.

16:9 - YouTube, Vimeo, TV. Standard horizontal widescreen format. The default for most video content and optimal for desktop viewing.

1:1 - Instagram Feed, Facebook Feed. Square format that works well in social media feeds and appears the same on desktop and mobile.

4:5 - Instagram Feed (portrait). Taller than square, this format takes up more screen real estate in Instagram feeds while remaining mobile-friendly.

21:9 - Cinematic Widescreen. Ultra-wide format for cinematic content. Common in movies and gaming.

Use Crop when: You want the video to fill the entire frame with no black bars. Best when the important content is centered or when you can sacrifice edge content. Social media algorithms often favor full-frame content.

Crop position matters. For videos with faces, choose "Center" or "Top" to keep faces in frame. For landscapes, "Center" usually works best. For action at the bottom, choose "Bottom".

Use Letterbox when: You need to preserve the entire original frame. Good for content where cropping would lose important information (text overlays, full-body shots, wide scenes).

Letterbox colors. Black is standard and looks professional. White works well for bright, minimalist content. Use the color picker to match your brand or create specific effects.

TikTok and Reels. Always use 9:16 vertical. Full-screen vertical content performs best. Crop rather than letterbox—black bars hurt engagement. Master TikTok optimization in our TikTok algorithm guide.

YouTube. Use 16:9 for standard videos, 9:16 for Shorts. YouTube adds black bars automatically if your aspect ratio doesn't match, so pre-formatting looks cleaner.

Instagram. Feed supports 1:1, 4:5, and 16:9. Stories and Reels use 9:16. 4:5 portrait takes up the most feed space and often performs best for engagement.

Multiple platforms. Creating content for multiple platforms? Start with 16:9 source footage and crop to each platform's format. This ensures maximum flexibility. Learn effective repurposing strategies in our content distribution guide.