Cropping cuts away the edges of a picture so only the part you want is left. This tool opens the photo in your browser and draws a crop box over it. Drag the box to move it, drag its corners or edges to resize it, or type the exact position and size in pixels. Ratio presets lock the box to common shapes: square 1:1 for profile and product photos, 4:5 for Instagram portrait posts, 16:9 for YouTube thumbnails and slides, 3:2 and 4:3 for camera prints, and 9:16 for stories. "Free" lets you draw any shape, and "Original" keeps the photo's own proportions.
The crop is pixel-exact: no resampling happens, so the part you keep has exactly the same detail as the original. By default the result is saved in the format you uploaded (a JPG stays a JPG, a PNG keeps its transparency, WebP stays WebP). iPhone HEIC and TIFF photos are saved as JPG, and GIF, BMP, SVG and PSD files as PNG, because browsers can't write those formats. You can pick another output format if you prefer.
Limits: one image per run. Animated GIFs are cropped as their first frame. Very large images (over about 16.7 megapixels, the most an iPhone browser can hold) are scaled down to that size before cropping. Saving re-encodes the image, which removes EXIF data such as the camera model and GPS location; JPG and WebP are saved at 92% quality.