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Compress PNG Online

Cut PNG file size by up to 80% and keep the transparency — still a real PNG, free, in your browser, with nothing uploaded.

Your file

Why use this tool

  • No file size limit
  • Nothing is uploaded
  • No signup needed

PNG is lossless: it stores every pixel exactly, which keeps logos and screenshots sharp but makes photographs and large graphics very heavy. A PNG saved from a design tool or a screenshot of a full screen easily runs to several megabytes.

A browser's own PNG encoder is lossless and ignores any quality setting, so simply re-saving a PNG never makes it smaller. This PNG compressor does what dedicated PNG optimizers do instead: it reduces the image to an optimized palette of up to 256 colors and writes a new, indexed PNG — the same dimensions, the same transparency, a fraction of the size. Everything runs in your browser; nothing is uploaded, and there is no account or watermark.

How to compress a PNG

  1. Add your PNG

    Drag the .png file into the box, or click to browse. Transparent PNGs are welcome.

  2. Set the quality

    80% is set for you. Lower it for a smaller file; raise it for sharp text and fine lines.

  3. Compress and download

    Press Compress PNG. You get a smaller .png file, its size and the percentage saved, ready to download.

How a PNG gets smaller and stays a PNG

PNG encoding is lossless, but reducing the palette before encoding can change colors. This tool chooses up to 256 colors and stores each pixel as an index into that palette. Compare gradients and edges with the original; smaller output is not guaranteed.

The palette is chosen by clustering the colors the image actually uses, and the colors are laid down with a light dither, so gradients stay smooth instead of breaking into bands. The quality slider sets how many colors are kept: 100% keeps the full 256, lower settings keep fewer for a smaller file.

Transparency is kept: every color in the palette carries its own opacity, so transparent backgrounds, soft shadows and anti-aliased edges survive. The result is an ordinary PNG that opens in every browser, image editor, CMS and upload form that takes PNG.

When another format is the better choice

Photographs are the one case where a palette struggles: a photo spreads smooth tones across millions of colors, and with 256 a fine grain can show at low settings. For a photo with no transparency, converting PNG to JPG is usually smaller still — typically a fifth to a third of the size, with transparent areas filled with white.

For images on a website, PNG to WEBP often goes further than any PNG can: WEBP keeps transparency and is read by every current browser. And if the image is simply bigger than it needs to be, resizing it saves the most of all — halving the width and height leaves a quarter of the pixels.

Original PNG compared with the compressed PNG

What changes, and what doesn't, when you compress a PNG here.

Original PNGCompressed PNG
File formatPNGPNG, unchanged
TransparencyYesYes, kept
DimensionsOriginalUnchanged
ColorsUp to millionsUp to 256, chosen for the image
File sizeLargeTypically 50–80% smaller
Opens inEverything that takes PNGEverything that takes PNG

When to compress a PNG

  • Images on a website

    Hero graphics, product cut-outs and illustrations saved as PNG are some of the heaviest files on a page. Compressed, they stay sharp and transparent at a fraction of the weight.

  • Screenshots for documentation

    Full-screen PNG screenshots add up quickly in help centers and tickets. Compressed, they load instantly.

  • Transparent logos and cut-outs

    Logos and product photos with the background removed keep their transparency after compression.

  • Staying under an upload limit

    When a form or platform insists on PNG and caps the file size, compressing gets a large PNG under the limit without changing its format.

Frequently asked questions

What does the quality slider do to a PNG?
PNG has no quality setting of its own, so here the slider decides how many colors the palette keeps: 80% keeps enough for most screenshots and logos to look unchanged, and lower values merge more shades into one. Press Compress PNG to see the saving.
Can I compress a PNG to a target size like 100 KB?
Yes. Pick Target file size and enter the limit; the palette is reduced until the PNG fits, and the image is only scaled down if fewer colors are not enough. The result card shows which happened. For a fixed 100KB budget there is also Compress PNG to 100KB.
Is the result still a PNG?
Yes. You download a standard .png file. It is an indexed PNG — the image is stored with a palette of up to 256 colors — which every browser, editor and upload form that accepts PNG can open.
Is transparency preserved when compressing a PNG?
Yes. Each color in the palette has its own opacity, so transparent backgrounds, soft shadows and semi-transparent edges stay as they were.
How much smaller will my PNG get?
Screenshots, logos, illustrations and graphics usually shrink by 50–80%. Photographs saved as PNG shrink too, but for a photo without transparency a PNG to JPG conversion is often smaller. A PNG that already uses few colors may barely change.
Will I see a difference in quality?
At the default 80% the difference is very hard to spot on most images. At low settings, smooth gradients can show a fine grain. The result card shows the saving before you download, so try two settings and keep the one you like.
What if the result is bigger than my original?
That happens when the PNG was already optimized — saved with a palette, or by a tool like this one. There is nothing left to remove, so keep your original.
Is my PNG uploaded anywhere?
No. The compression happens on a canvas in your browser tab, and the file never leaves your device.
Can I compress a JPG on this page?
This page takes PNG only. JPG and JPEG photos have their own page, Compress JPG, which keeps them as JPG.

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