Compress JPG

JPG compression is lossy, so each setting trades a little detail for size. The controls below are preset to keep your files in the JPG format.

1. Drop JPG photos on the box, paste them, or click to choose. Add as many as you like.
2. Set Quality. The default is 75. Lower numbers give smaller files and a softer look.
3. Enter a Max width in px (0 = keep size) if the photos are larger than you need. Leave it at 0 to keep the original dimensions.
4. Keep Output format on Same as input, which is already chosen for this page.
5. Press Compress JPG, read the before and after sizes, then download. The files keep their original names, so save them to a different folder.

File size follows the number of pixels more closely than most people expect. A 4000 by 3000 photo has 12,000,000 pixels. Shrink it to 1600 pixels wide and it becomes 1600 by 1200, which is 1,920,000 pixels, only 16 percent of the original. Halving the width, say from 4000 to 2000, removes 75 percent of the pixels. A lower quality setting then squeezes what is left.

As an illustration, a phone photo of 3.8 MB might drop to about 1.5 MB at quality 75 alone, and to a few hundred KB if you also cap the width at 1600. Those figures are examples, since results vary with the picture, and the tool prints your real numbers. Max width only shrinks; a picture narrower than the limit is left at its own size.

When a form asks for a specific size such as 200 KB, the reduce image size in KB page searches for the right quality automatically.

Compressing is a one-way change, so keep your untouched photos. Several side effects are worth knowing about:

• Repeated compression adds up. Each pass through a JPG compressor discards more detail. Compress from the original once rather than re-compressing a file that was compressed before.
• Some files grow. A JPG that was already saved at low quality can come out larger at 75. The tool shows a percentage larger or smaller, so check it.
• Metadata is removed. The photo is redrawn in the browser, so camera model and GPS data are not kept. Phone rotation is applied to the pixels, so the picture still opens upright.
• Transparency does not apply. JPG has none, and any clear pixels become white.
• Dimensions only shrink. The Max width control never enlarges a picture, so a small image stays as it is, and only the quality setting affects it.
• Name collisions are easy. The compressed file has the same name as the original, so a download into the same folder may be renamed by your browser or replace the file you meant to keep.

For PNG files use Compress PNG, which works differently, and for exact pixel sizes use the image resizer. If the main aim is privacy, the EXIF data remover lists what was found in each picture. The general image compressor also accepts WebP and PNG. All processing is local to your device.

These are starting points, not rules. Compress one photo, look at it, and adjust.

If a form wants a precise limit, such as 200 KB, set a target on the reduce image size in KB page instead of guessing, because it adjusts the quality for you. A phone with a very high resolution camera produces files far larger than any screen needs, so a width cap alone often does the job.