Free Creator Tool · Resize
Aspect ratio calculator for video
Reframe between horizontal and vertical, square and cinematic — get exact pixel dimensions for crop, letterbox and recommended export in a single view.
Visual preview
Target frame at 1080×1920
Crop / fill
1920 × 3413
Fills the target — crops source
Letterbox / fit
608 × 1080
Keeps full source — adds bars
Recommended export
1080 × 1920
At target ratio, long edge preserved
Math is done locally in your browser — nothing is sent anywhere.
When to use this
Every time a YouTube cut gets repurposed for TikTok, Reels, or Shorts you face the same math: what's the right canvas size, where do I crop, and what do I lose? This tool answers all three at once from any source resolution and any target ratio.
Crop / fill gives you the dimensions that the source fills the target with — you lose some of the frame on the long side but there are no black bars. Letterbox / fit keeps the whole source visible — black bars top/bottom or left/right. The recommended export rounds to even pixels so most encoders won't complain.
Reframing manually is a few minutes of math per delivery. Yond Resize in the YondCut Premiere Pro plugin does it in one click using Premiere's Sensei AI — and keeps subjects centered as they move.
Frequently asked questions
Power up with YondCut
Auto-reframe with motion tracking
Yond Resize takes your 16:9 sequence and creates 9:16, 1:1, 4:5 versions in one click — keeping subjects centered through the entire cut.