ClickyApps

Aspect Ratio Converter

Render vertical, square, or widescreen exports with smart pad & crop in-browser.

Tip: Your data stays in your browser.
Drop a video or browse

MP4, MOV, WebM up to 150 MB / 12 minutes. We process everything locally.

Want to try it first? Load the demo clip from the Examples list below.

Examples

Preview
1080×1920 • 9:16 • Smart → pad
MP4 (H.264 + AAC)
Upload a clip to preview
Target
1080×1920
Ratio 9:16
Handling
Smart → pad
Adds bars to keep the full frame.
Format
mp4
Match source fps • CRF 18

FAQs

  • Does my video leave the browser?
    No. Uploads, rendering, and downloads happen locally in your browser — nothing is sent to our servers.
  • What file sizes and lengths are supported?
    Clips up to roughly 150 MB or 12 minutes work smoothly in-browser. Larger files are better handled in a desktop editor.
  • What export formats can I choose?
    Choose MP4 (H.264 + AAC) for universal uploads or WebM (VP9 + Opus) for smaller files and embeds. You can also set target FPS and bitrate.
  • How does Smart Fit decide between padding and cropping?
    Smart Fit compares the source and target aspect ratios: wider footage crops to fill vertical frames, taller footage gets padded. You can always override this behaviour.
  • Can I customise the padding style?
    Yes — pick any hex colour for letterboxing, toggle the safe-area overlay, and share those settings with teammates via the share link.
  • Will my audio be changed?
    Audio is re-encoded to AAC (MP4) or Opus (WebM) at upload-friendly bitrates so your export is ready to post immediately.

Guides

YouTube Thumbnail Size and Ratio (2025)
Exact dimensions, aspect ratios, and export settings for YouTube, Shorts, and Instagram thumbnails—with quick presets and quality checks.
Read →
Safe Text Areas for Thumbnails (YouTube/Shorts/Instagram)
Keep your thumbnail text readable across all devices by positioning it inside safe zones—with practical margin guides, platform-specific overlays, and real-device validation using Thumbnail Resizer.
Read →
Contrast & Legibility for Thumbnail Text (2025)
Make thumbnail text readable on any feed with practical contrast targets, safe-area framing, and fast fixes using Thumbnail Resizer and Contrast Checker.
Read →
Design Once: Export 16:9, 9:16, and 1:1 Thumbnails (2025)
Design your thumbnail once, then export perfect 16:9, 9:16, and 1:1 versions without rework using presets, safe-area guides, and consistent framing.
Read →
Thumbnail Color Pairings that Pop Without Artifacts (2025)
Build high-contrast color combinations that survive compression and platform overlays using Contrast Checker, plus workflows to keep edges clean on every export.
Read →
Strokes, Shadows, and Outlines: Thumbnail Legibility Toolkit (2025)
Build stroke, shadow, and highlight-plate stacks that keep thumbnail text readable on every feed using Contrast Checker plus fast mobile checks.
Read →