JPEG Compressor

Compress JPEG photos to a fraction of their size with a quality slider and instant before/after readouts — all on your device, never uploaded.

Drop JPEG files here

or — multiple files welcome. Nothing is uploaded; conversion happens on your device.

Files are processed entirely in your browser — never uploaded, never stored. Large photos convert in about a second each; the first HEIC file loads a small decoder module.

Runs fully in your browser — images are never uploaded or stored.

Frequently asked questions

How much can I compress a JPEG without visible quality loss?

Most photos survive 70–80% quality with no visible difference at normal viewing sizes — routinely cutting file size by half or more. Below ~60% you’ll start to see softness and blockiness in detailed areas. The before/after sizes update as you adjust.

How do I compress a JPEG to a specific size like 100 KB?

Lower the quality slider and re-convert until the output lands under your target — the size readout updates per file. Very large photos may also need downscaling to hit small targets.

Does compressing again and again ruin photos?

Each re-encode loses a little more — generation loss. Compress once from the best original you have rather than repeatedly re-compressing compressed files.

Are my images uploaded to a server?

No. Conversion runs entirely in your browser using its built-in image engine — files never leave your device, which also makes it faster than upload-based converters and safe for private photos.

Embed this calculator

Free to embed on your site. The attribution link back to this page is required — please keep it visible.

<iframe
  src="https://stopbyte.com/embed/compress-jpeg"
  title="JPEG Compressor by StopByte"
  width="100%" height="640" style="border:1px solid #d9dde3;border-radius:12px"
  allow="clipboard-write" loading="lazy"></iframe>
<p>Calculator by <a href="https://stopbyte.com/tools/compress-jpeg">StopByte JPEG Compressor</a></p>