Crop a JPG photo, image or picture without compressing it again. Out comes a JPEG whose blocks inside the box are the original file's blocks, copied byte for byte, so the crop is exactly as sharp as the photo was.
Re-saving a JPEG after cropping usually compresses it a second time, which softens detail and adds artefacts. Here the compressed data is copied instead. The one condition is that the left and top edges sit on the JPEG's own 8 or 16 pixel block grid, so the box snaps to it.
Exact pixels without the block grid: crop by pixels. A PNG kept exact: crop PNG. A JPG under a KB limit (which needs a re-encode): crop and resize.
What you can do here
The original data, copied
A JPEG is stored as 8×8 blocks of compressed data. Inside the box those blocks are copied as they are; nothing is decoded and compressed again.
Edges on the block grid
The left and top edges snap to the 8 px grid (16 px for most phone photos). The right and bottom edges stay exactly where you put them.
Metadata your choice
EXIF, camera and location data are stripped by default; one switch keeps them. The colour profile always stays.
Honest when it cannot
A shape, a straighten angle, a resize or a KB target needs new pixels, so lossless pauses and says why; the ordinary crop is used instead.
How to crop jpg online
- 1Open the JPG
Drop it on the box. It is read in this tab.
- 2Drag the box
The left and top edges snap to the block grid as you move it. Keep Lossless on under Export; it shows the grid size it is using.
- 3Download
The contract says Lossless: no re-encode, the grid size and the bytes. Download saves the copied file.
Questions about cropping
What does a lossless JPG crop mean?
The file's compressed data inside the box is copied into a new JPEG without decoding it to pixels and compressing it again. Every block inside the crop is the original block, so there is no further loss of quality and no new artefacts.
Why do the edges jump by 8 or 16 pixels?
JPEG stores the picture in blocks of 8×8 pixels, grouped into 16×16 when colour is stored at half resolution, as most phone photos are. A crop can only start on a block boundary, so the left and top edges snap to that grid. The right and bottom edges are free.
Is EXIF kept?
By default no: camera details, dates and location are stripped, because a cropped photo is often shared. Turn on Keep the original metadata to copy them. A photo stored sideways keeps its orientation tag either way, so it opens the right way up.
When is lossless not possible?
When the crop needs new pixels: a shape, an outline, a border, a straighten angle, a quarter turn or mirror, an output size other than the crop, a KB range, or a requirement that writes a density. The page says which one paused it, and the ordinary crop is saved instead.
Which JPEGs does it work on?
Baseline and progressive JPEGs with Huffman coding, which is almost every JPEG from a camera, phone or the web, in colour or greyscale. The rare arithmetic-coded and lossless-mode JPEGs are refused with a sentence.
Why is the file sometimes bigger or smaller than I expect?
The copied blocks are re-packed with compression tables built for the cropped part, so the file is roughly the original's bytes per pixel, sometimes a little less. Its size is in the contract before you save.