Crop to 1:1.414 (A4 proportions)
Drop an image and crop it to 1:1.414, the proportions of the ISO A-series used across most of the world, including A4. The figure is the square root of 2, which is what lets an A3 fold down to A4 to A5 with the same shape each time.
This is the crop for an image that needs to fill an A4 page in portrait. Each image opens in an editor where you drag to reposition the subject and zoom from 1× to 8×, with a rule-of-thirds grid and Center to help.
What you get
- Original format kept. JPEG stays JPEG, PNG keeps transparency, WebP stays WebP.
- Full resolution. Only the area outside the frame is removed.
- A-series output sized to the largest 1:1.414 region that fits your framing.
Batch and privacy
Add several images, frame each, and use Download all as ZIP, or download one at a time. Everything runs in your browser; nothing is uploaded.