A JPG straight from a phone or camera can be several megabytes — more than you need for email, a website, or a form with a size limit. This compressor re-encodes your JPG at a leaner quality that typically halves the file (or better) while keeping the photo looking sharp at normal viewing sizes. It is the fastest way to get under an upload cap without resizing.
What the JPG quality slider really trades away
JPG compression works by grouping pixels into small blocks and discarding the high-frequency detail your eye is least likely to miss. Dialling quality down tells the encoder to be bolder about what it throws out. At gentle settings the savings are huge and the loss is invisible; push too far and you start seeing tell-tale blocking and halos around sharp edges. This compressor sits in the sweet spot where photographs typically halve in size with no perceptible change at normal viewing distance. The catch is cumulative: re-compressing an already-compressed JPG stacks loss on loss, so always compress from the best original you have. When a file needs to stay pristine for editing, convert it with JPG to PNG first instead of squeezing it repeatedly.
Compress, resize, or both to beat an upload cap
When a form rejects your photo for being too large, you have two levers. Compression keeps the same dimensions but stores them more tightly, ideal when the resolution genuinely matters — a detailed scan, say. Resizing reduces the pixel count itself, which is the bigger hammer for a phone photo that is far larger than it will ever be displayed. Often the best result combines them: scale down with the JPG resizer, then run this compressor on the smaller image. For images already inside jpgoo as another format, start at Convert to JPG to normalise everything first, then compress. Most upload limits fall away after a single compression pass, no resizing required.