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Compress

Compress PNG. For free.

Shrink a heavy PNG so it loads fast. In our tests a screenshot came out 75% smaller and a photo 73% smaller, with transparency kept. Stays a PNG, no watermark, no signup, and if the result is not smaller we hand back your original, never a bigger file.

Screenshot 75% smallerTransparency keptNo signup or watermarkDeleted after 1 hour

Never bigger

Keeps the smaller of the two

Private

Encrypted upload, our own engine

Temporary

Deleted after 1 hour

How it works

  1. 01

    Add your PNG

    Drop in a PNG, or click to browse. Uploaded privately over TLS.

  2. 02

    We compress it

    We rebuild the PNG with a palette of at most 256 colours and the strongest zlib setting. Transparency is kept.

  3. 03

    Download the smaller PNG

    See exactly how much you saved, then grab the lighter file. Everything is deleted after 1 hour.

Also compress: JPG · any image · PDF.

Common questions

How much smaller will my PNG get?+

We measured three files on the engine this page uses. A 1440 by 900 screenshot went from 400 KB to 98 KB, 75% smaller. A 1920 by 1200 photo saved as PNG went from 1,469 KB to 394 KB, 73% smaller. A 1024 pixel logo with a transparent background went from 99 KB to 88 KB, only 11% smaller, because it had few colours to begin with. If the result is not smaller, we tell you and hand back your original, never a bigger file.

Does it keep transparency?+

Yes. The output keeps its alpha channel, so transparent areas stay transparent. Soft edges are rounded to the nearest palette entry along with the colours: on our logo test the most any edge pixel moved was 70 of 255 opacity levels.

Does it change the pixels?+

Yes, slightly. Cutting the image down to a palette of at most 256 colours changes pixel values. Flat graphics barely show it: our screenshot fell from 11,543 colours to 43 and looked the same, with an average change under 1 level in 255. A photo is held to 256 colours, so smooth skies and gradients can show banding. For photos, JPG or WebP is the better format, and it stays smaller too.

Does it stay a PNG?+

Yes. The file comes back as a PNG with the same width and height. To switch to a smaller format such as WebP, use our converters instead.

Is my image private?+

Yes. Uploaded over an encrypted connection to our private storage (Supabase, named in our privacy policy), compressed on our own server, never by an outside conversion service, and deleted after 1 hour.

Is there a limit?+

No watermark and no signup. Free covers 10 server conversions a day, up to 100 MB a file. Pro removes the daily limit and raises the file limit to 2 GB.