Fast workflow
Designed to reduce friction with direct upload, quick processing, and one-click export.
Open Video Aspect Ratio, add your file, then choose the target output and run conversion.
This tool is optimized for video processing and works best with mp4, avi, mov, mkv, webm as inputs.
When processing completes, download the result in mp4, webm, avi and verify quality before sharing.
Video Aspect Ratio is a privacy-first utility for fast video processing. It helps you move from mp4, avi, mov, mkv, webm to mp4, webm, avi with consistent output quality.
Designed to reduce friction with direct upload, quick processing, and one-click export.
Files are handled in an isolated processing flow with minimal retention and clear user controls.
Outputs are tuned for real use cases across mp4, webm, avi.
A predictable sequence keeps conversion stable across devices and file sizes.
Video Aspect Ratio accepts mp4, avi, mov, mkv, webm and exports mp4, webm, avi.
The pipeline is designed for privacy-first processing with clear user control over inputs and outputs.
Use high-quality source files, choose the closest matching target format, and avoid repeated reconversion cycles.
Video Aspect Ratio follows a deterministic conversion flow so results are repeatable and easier to troubleshoot when a file behaves unexpectedly.
Change a video's aspect ratio by padding with black bars or cropping.
All uploads are processed on secure ConvertCraft servers with encrypted transfer. Original files are permanently deleted from our servers immediately after processing — no copies are retained. Processing happens in isolated containers that are destroyed after your session.
This tool uses FFmpeg's scale, pad, and crop filters to reframe video content. The Pad method applies the scale filter followed by pad with configurable colour (default black) to add horizontal letterbox or vertical pillarbox bars. The Crop method calculates the largest rectangle matching the target ratio within the source dimensions, using centre-gravity positioning by default. Supported ratios include 16:9 (widescreen), 9:16 (mobile portrait), 1:1 (square), 4:3 (classic TV), and 21:9 (ultrawide cinematic).
Essential for repurposing content across platforms — a 16:9 YouTube video needs 9:16 padding or cropping for TikTok Reels and Instagram Stories. Also useful for adding cinematic 21:9 letterbox bars to standard footage, or converting 4:3 legacy content to modern 16:9 without distorting the image. Perfect for matching broadcast specifications or social media upload requirements.
See the detailed comparison guide or try a related tool:
MP4, MOV, AVI, MKV, WebM and more