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Compress Image

Reduce image file size with an adjustable quality setting, showing the real saving.

Compress Image

Reduce image file size while maintaining quality.

What Compress Image does

Large images are the most common cause of slow web pages and of email attachments that bounce. Compression re-encodes the picture with less data, and the quality setting controls how much detail is discarded.

The relationship is not linear. Dropping from maximum quality to around 80 percent typically removes more than half the file size with little visible difference, while pushing much below 60 starts to show blocking and haloing around edges.

  • Quality slider from 1 to 100
  • Before-and-after file sizes
  • Accepts PNG, JPEG and WebP

How to use Compress Image

  1. 1

    Add your image

    Drop in a PNG, JPEG or WebP file.

  2. 2

    Set the quality

    Start around 80. Lower it while watching the preview until quality becomes unacceptable, then step back.

  3. 3

    Compare the sizes

    The saving is shown as a real byte figure, not an estimate.

  4. 4

    Download the result

    Keep your original: compression cannot be undone.

When to use it

Speeding up a web page

Images are usually the largest thing a page loads, so compressing them is the highest-impact performance change available.

Getting under an upload limit

Forms and email systems frequently cap attachments at a few megabytes.

Limits and known behaviour

  • Compression here produces a JPEG, so a PNG with transparency has its transparent areas filled with white.
  • The process is lossy and irreversible. Detail removed is gone, and re-compressing an already compressed image adds artefacts for very little further saving.
  • Only quality is adjustable. There is no resizing, and reducing the pixel dimensions is often the bigger win for a photograph that is far larger than the space it will be displayed in.
  • Supported formats are the ones your browser can decode and encode: PNG, JPEG and WebP. HEIC from iPhones, AVIF, TIFF and RAW camera files are not supported.
  • Very large photographs can be slow to process on a low-powered device, since the whole image is decoded in the page.

Privacy and data handling

Runs entirely in your browser

  • Your image is decoded and redrawn by the browser inside this page. It is never uploaded.
  • Compression re-encodes the picture, which does not deliberately preserve EXIF metadata such as GPS coordinates, but you should not rely on it as a way to strip metadata.
  • Nothing is stored; the file and the result disappear when you close the tab.

Site-wide data handling, including analytics and advertising, is described in the privacy policy.

Frequently asked questions

What quality setting should I use?

Around 80 for photographs on the web is the usual recommendation: a large saving with differences most people cannot see. Text, screenshots and flat graphics need higher settings, because JPEG artefacts are much more visible around sharp edges.

Why did my transparent PNG get a white background?

The output is JPEG, and JPEG has no transparency. White is filled in rather than leaving the area black. To keep transparency, use the converter to produce PNG or WebP instead.

Can I get my original quality back?

No. Lossy compression discards information permanently, which is why you should always keep the original.