Every ad needs to ship in multiple aspect ratios: 1x1 for legacy placements, 4x5 for Instagram feed, 9x16 for stories and Reels, 16x9 for YouTube and desktop video, 21x9 for email banners. Doing this by hand is the kind of repetitive task that eats afternoons. Magic Resize does it in one click. Pick the aspect ratios you want, and the agent generates a properly-composed version of your image for each one — re-laying out the elements rather than just cropping the original.Documentation Index
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Why this is different from cropping
Cropping (what Meta does automatically when you don’t supply the right format) frequently kills the composition. Subjects get clipped at the edge, copy gets cut off, hero products get pushed out of frame. The platforms’ auto-crop logic is good but not great, and most performance teams want control over how their ads adapt. Magic Resize uses an AI pass to actually re-compose the image — moving the subject, repositioning copy, regenerating the background as needed — so each aspect ratio looks intentionally designed rather than algorithmically cropped.The workflow
Hit Magic Resize
A grid of aspect ratio options appears: 1x1, 4x5, 9x16, 16x9, 4x3, 3x4, 21x9, and so on. Click each one you want generated.
Run
The agent generates each variant in parallel. New image nodes appear on the canvas — one per selected aspect ratio — all connected back to the original.
Standard ad formats by channel
If you’re not sure which ratios to generate, the common defaults:- Meta feed (Facebook/Instagram): 1x1 or 4x5
- Meta stories/reels: 9x16
- Meta in-stream video: 16x9 or 4x5
- TikTok/Reels: 9x16
- YouTube pre-roll: 16x9
- LinkedIn feed: 1x1 or 16x9 (1.91:1 specifically)
- Display banners: varies — 300x250, 728x90, 160x600 are common, but most are close enough to 1x1, 21x9, and 4x5 respectively
- Email banners: 21x9 is a good default for hero banners that need to fill the width without scrolling below the fold
Working with Magic Resize on multiple images at once
If you have a batch of finished ads on the canvas, you can apply Magic Resize to all of them in one agent brief:When Magic Resize isn’t the right move
A few cases where it’s better to regenerate from scratch rather than resize:- The composition logic is fundamentally different per channel. A 16x9 video frame and a 9x16 story sometimes need entirely different shot composition, not the same shot reflowed. Generate them separately from the same brief.
- The aspect ratio change requires major background extension. Going from 9x16 to 21x9 forces the model to invent a lot of background. The result is usually fine for environmental shots but can break for tight portrait or product compositions.
- You haven’t finalized the source image yet. Don’t resize a draft — the resizing pass also locks in compositional choices you might still want to change.
Common pitfalls
- Selecting too many aspect ratios. Pick the channels you actually ship to. Eight aspect ratios of a draft is forty seconds of waste; eight aspect ratios of every variant in a 50-variant batch is real time.
- Resizing at 1K and shipping it. Make sure your output resolution is set to 2K (or higher) on the Magic Resize variants before downloading. The on-canvas preview is downscaled — what you see isn’t the final resolution.
- Forgetting to brand-check the resized versions. A composition that worked at 9x16 might push your logo or CTA off-canvas at 1x1. Spot-check every variant before shipping.