No upload, 100% local, no account

Compress images

Reduce file size locally: quality slider or target KB. Batch supported. Nothing leaves your device.

How Compress images works

Shrink the file size of your photos directly in your browser, with the same WebAssembly codecs used by professional tools (MozJPEG, OxiPNG, WebP). The compressor accepts JPEG, PNG, WebP, AVIF, GIF, BMP and TIFF files up to 50 MB, and can keep the original format or convert the output to JPEG, WebP or AVIF, which often saves more at the same visual quality.

Two modes cover the two real-world situations. In quality mode you set the level yourself (the default of 82 is a good starting point for photos) and compare the result. In target-size mode you type any maximum size in kilobytes you need, 100 KB fits most email attachment limits, 50 KB clears a typical web upload form, 20 KB suits a tight avatar or thumbnail cap, and the tool searches for the highest quality that fits under that number by re-encoding at different levels, so you do not have to guess. The result lists the size before and after with the exact percentage saved, before you download anything. Very small targets on detailed photos will visibly soften the image; that trade-off is inherent to lossy compression, and if the result looks too soft you can simply re-run the same photo at a higher quality.

Written by Bastien Sulyan

How to use Compress images, step by step

  1. Open the Image Compressor page in your browser: no installation or sign-up needed.
  2. Drop your image onto the upload zone or click to browse. Accepted formats: JPEG, PNG, WebP, AVIF.
  3. Choose your output format and drag the quality slider to balance size against visual fidelity.
  4. Optionally set a maximum file-size target in KB; the tool will re-encode until the constraint is met.
  5. Click Compress, then Download to save the result. The original is never sent to a server.

Common use cases

  • Shrink a product photo to fit an e-commerce upload limit without losing visible quality.
  • Reduce a hero image's weight before deploying a web page to improve load time.
  • Compress sensitive photos (ID scans, medical images) locally so they never leave your device.
  • Batch-lighten press-kit images before attaching them to an email.

Frequently asked questions

Are my files uploaded to a server?

No. Your image is decoded into an OffscreenCanvas and re-encoded by jSquash WebAssembly codecs (MozJPEG, OxiPNG, WebP) entirely inside this browser tab, read from your device, compressed in memory, and handed back as a local download. Nothing reaches Sunasty or any third party. Open your browser DevTools, go to the Network tab and watch: no request carries your image.

How small can I make my images?

You can drive the quality slider down or set a target size in KB. The tool tries to meet your target by lowering quality; very small targets on detailed photos may visibly soften the image, which is an inherent trade-off of lossy compression, not a limitation of doing it locally.

Does compressing strip metadata like GPS location?

Re-encoding generally produces a fresh file without the original EXIF block, but if you specifically want to inspect or remove metadata, use our EXIF reader for an explicit, verifiable result.

Does it work offline?

Mostly, yes. The processing itself always runs on your device, so your files never leave your machine. The one caveat: this tool's engine is a sizeable download, fetched from our site the first time you use it. Once the page and the engine have been fetched, you can disconnect from the network and the tool keeps working.

Is it free? Do I need an account?

It is completely free and requires no sign-up. There are no watermarks, no daily limits and no tracking cookies needed to use the tool.

Can I compress images on my phone?

Yes. The compressor is a web page, so it works in mobile Chrome or Safari the same as on a computer, including photos taken directly with the phone camera. The jSquash codecs are a first-use download (see the offline answer above), which uses mobile data unless you are on Wi-Fi the first time.