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Compress PNG

Pick how many colours the PNG may use and watch the size drop. Transparent edges stay transparent, and nothing is uploaded.

Drop, paste or pick an image

JPG · PNG · WebP · AVIF · HEIC — up to 50 MB

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Settings

Colours

Fewer colours = smaller file. 256 suits most graphics; photos may show banding below 128.

Original
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Result
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Processing runs in this tab. Your images are never uploaded to a server.

PNG colour count: how many colours does your image need?

A regular PNG can hold millions of colours. Most logos, icons and screenshots use far fewer, so storing them in a small palette shrinks the file without a visible change.

ColoursSuitsWhat to watch
LosslessPixel-exact assets, photos you must not alterOnly re-encodes; savings are usually small
256Screenshots, UI mockups, illustrations with gradientsRarely distinguishable from the original
128Web graphics, charts, most product cut-outsSoft gradients may start to band slightly
64Logos, icons, diagrams with flat fillsCheck shadows and anti-aliased text
32Simple icons, line art, two-tone badgesGradients turn into visible steps
16Pixel art, favicons, very flat graphicsOnly for images that really have few colours

The saving depends on the picture. Try a lower setting, check the before/after slider, and step back up if you see banding.

Palette PNG in plain words

Instead of storing a full colour for every pixel, the file stores a short list of colours and each pixel points to one of them. Fewer entries means less data.

Flat graphics gain the most

Logos and UI screenshots have large areas of identical colour, so they drop to a palette with almost no visible change.

Photos in PNG are a special case

A photo saved as PNG has too many shades for a small palette. Keep it at 256 colours or convert it to JPG or WebP instead.

Transparency stays intact

Reducing colours does not flatten your PNG onto a background. The alpha channel is part of the palette, so cut-outs keep working on any page colour.

Soft edges are kept

Semi-transparent pixels around a logo or product are stored as palette entries with their own opacity, so edges don't turn jagged.

Test on dark and light

After compressing, place the PNG on both a white and a dark background. Faint halos are the first sign that the colour count is too low.

No white fill added

Unlike a JPG conversion, nothing is painted behind the image. What was see-through in the original stays see-through.

Getting the smallest PNG for your use

Colour count and pixel dimensions work together. Combine them for the lightest file that still looks right where it will be shown.

Resize before you reduce

A 4000 px screenshot shown at 1200 px wastes data. Set the longest side first, then choose the colour count.

No dithering, clean flats

The tool maps each pixel to the nearest palette colour without adding noise patterns, which keeps flat areas clean and compresses well.

When to stop using PNG

If a photo still weighs several megabytes at 256 colours, the format is the problem. A WebP or JPG will be far lighter.

Compress PNG: questions

How does this PNG compressor make files smaller?

It reduces the image to a limited palette of colours, the same idea behind popular lossy PNG optimisers, then writes a new PNG. Fewer distinct colours means much less data to store.

Will I lose transparency when I compress a PNG?

No. Opacity is stored in the palette alongside each colour, so fully and partly transparent pixels are preserved in the compressed PNG.

Which colour setting should I start with?

Start at 128 for most graphics and 256 for screenshots with gradients. If the before/after slider shows no difference, try the next step down.

What does the Lossless option do?

It re-encodes the PNG without changing a single pixel. That removes inefficient encoding and extra chunks, but the saving is modest compared with a colour reduction.

Why do I see stripes in the sky of my PNG?

That is banding: a smooth gradient needs more shades than the palette allows. Move up to 256 colours, or save photographic images as JPG or WebP.

Can I compress PNG files for a website logo or favicon?

Yes. Logos usually look identical at 64 colours or fewer, and pixel-perfect favicons can go as low as 16. Keep a lossless copy of the master file for later edits.

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