Fit Within Box

Scale images to fit entirely within a specified bounding box while preserving their original aspect ratio—equivalent to CSS object-fit: contain behavior. The image scales down only as much as necessary so that both width and height remain within your maximum limits, with no cropping and no distortion. Portrait, landscape, and square images all fit properly within the same bounds.

The algorithm compares the image's aspect ratio to the bounding box's aspect ratio to determine which dimension is the constraint. If the image is wider relative to the box, width becomes the limiting factor and height scales proportionally. If the image is taller relative to the box, height constrains and width follows. Images already smaller than the box in both dimensions remain unchanged (unless you enable upscaling). The result fits completely inside your specified bounds with guaranteed proportional accuracy.

Platform administrators enforcing upload size limits ("images must not exceed 2000×2000") ensure all uploads comply regardless of source dimensions or orientation. Thumbnail generation systems producing previews that fit within allocated spaces handle mixed-orientation source images consistently. Email template designers constraining images to maximum dimensions for reliable rendering across email clients prevent layout-breaking oversized images. Gallery applications displaying images in fixed-size containers fit each image appropriately without cropping important content. Document management systems with dimension requirements for attachments validate and resize uploads automatically. Anyone needing guaranteed maximum dimensions while preserving full image content and correct proportions will find bounding-box fitting the most reliable approach.