About Social Video Aspect Ratio Converter & Padder
Calculate dimensions and simulate letterbox/pillarbox padding when converting videos between 16:9 (YouTube), 9:16 (Shorts/TikTok/Reels), 1:1 (Square), and 4:5 (Instagram). Includes ready-to-use FFmpeg terminal commands.
Key Capabilities & Features
- Interactive aspect ratio converter for 16:9, 9:16, 1:1, 4:5, 4:3, and 21:9
- Live visual pillarbox and letterbox simulator with color picker
- Greatest Common Divisor (GCD) and decimal ratio analytics
- Automatic target resolution calculations (1080p, 4K, 720p)
- Generates copy-paste FFmpeg terminal commands for zero-reencoding padding
How to Use Social Video Aspect Ratio Converter & Padder
Enter Original Dimensions
Type in source video width and height (e.g. 1920x1080).
Choose Target Ratio
Select 9:16 for vertical Shorts/TikTok or 1:1 for square feed.
Copy FFmpeg Command
Use the generated terminal command to process your video with custom padding.
Privacy & In-Browser Execution Guarantee
100% Client-Side. Aspect calculations and command generators run entirely in your browser.
Frequently Asked Questions
What is the difference between letterboxing and pillarboxing?
Letterboxing adds black bars to the top and bottom of a widescreen video, while pillarboxing adds bars to the left and right sides when fitting a video into a wider container.
How does aspect ratio conversion handle mismatched frame sizes?
You can choose between Contain (letterbox padding with custom blurred or solid backgrounds), Cover (cropping center subject to fill the canvas), and Stretch (proportional distortion).
Can I calculate exact padding pixels for video editing software?
Yes. The tool outputs precise pixel padding values (top, bottom, left, right) and CSS/FFmpeg coordinate snippets for seamless import into Premiere, DaVinci Resolve, or Final Cut.