To compress a PNG online, add your PNG files above, choose Smart (256 colours) for the best balance or Lossless to keep identical pixels, then press Compress. Free, private, and your images are never uploaded.
Add your images, choose the settings and download smaller files. Everything runs in your browser, so your images are never uploaded.
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To compress a PNG online, add your PNG files above, choose Smart (256 colours) for the best balance or Lossless to keep identical pixels, then press Compress. Reducing the colour palette is what makes PNG files much smaller. Transparency is kept and nothing is uploaded.
Shrink PNG screenshots, logos and graphics while keeping their transparency. Choose smart colour reduction for the biggest saving, or lossless re-compression when every pixel must stay exactly the same. It is a free tool from Websolindia, a New Delhi website design and SEO company that builds fast, image-optimised websites.
Unlike most online image tools, this one does not upload your pictures. Your browser decodes each image, re-encodes it with an open-source compression engine and shows you the exact before and after sizes. You can process up to 30 images at a time and download them one by one or together as a ZIP.
Once your image is ready, you may also want the JPG Image Compressor Online, the WebP Image Compressor Online or the PNG to WebP Converter Online. All of our free image tools are listed in the Image Compressor Tools collection and the Websolindia Image Converter.
Use this table to choose settings with confidence.
| Mode | Colours kept | Pixels identical? | Best for |
|---|---|---|---|
| Smart | 256 | Visually, yes | Most graphics and screenshots |
| Strong | 128 | Very close | Simple graphics, icons |
| Stronger | 64 | Close for flat art | Logos, flat illustrations |
| Maximum | 32 | Visibly simplified | Tiny icons, smallest files |
| Lossless | All | Yes, exactly | Archiving, pixel-exact work |
This is exactly what happens to your image, with no hidden step. You can check that nothing is uploaded by watching your browser's network tab while you use the tool.
| Step | What happens |
|---|---|
| 1. Read and decode | The PNG is decoded to RGBA pixels, including its transparency. |
| 2. Resize (optional) | A maximum width scales larger images down with a Lanczos filter; images are never enlarged. |
| 3. Reduce the palette | In the lossy modes, the image is quantised to the number of colours you chose using the UPNG.js quantiser, keeping partial transparency. |
| 4. Pack the data | Pixel rows are filtered and compressed with DEFLATE to produce a standard PNG file. |
| 5. Compare with the original | If the new file is not smaller than your original, we return your original instead. |
| Setting | Default | Choices | What it does |
|---|---|---|---|
| Compression | Smart — 256 colours (best balance) | Smart — 256 colours (best balance); Strong — 128 colours; Stronger — 64 colours; Maximum — 32 colours; Lossless — identical pixels | Colour reduction is what makes PNG files much smaller. Lossless keeps every pixel exactly. |
| Maximum width in pixels (optional) | Empty | 1 to 20000 | Larger images are scaled down, never up. |
| What | Formula | Notes |
|---|---|---|
| Size change | (new − original) ÷ original × 100 | Shown for every file. |
| Palette size | Number of colours N, 2 ≤ N ≤ 256 | Fewer colours means a smaller file and less colour detail. |
| Component | Role | Where it runs |
|---|---|---|
| UPNG.js | Colour quantisation and PNG packing | Your browser |
| pako (DEFLATE) | Compression of pixel rows | Your browser |
| Topic | Detail |
|---|---|
| Images per batch | Up to 30 at a time |
| File size | Up to 150 MB per image |
| Image dimensions | Up to about 120 megapixels; larger images are declined to protect your browser |
| Privacy | Images are processed in your browser and never uploaded |
| Browsers | Current Chrome, Edge, Firefox and Safari (WebAssembly is needed for AVIF, HEIC, TIFF and AI tools) |
| Metadata | EXIF and location data are not copied into new files |
Smart, Strong and Maximum reduce the colour palette, which is lossy but often invisible on flat graphics. Lossless mode keeps every pixel identical and only changes how the data is packed.
Yes. Transparent and semi-transparent pixels are kept in every mode.
Graphics with few colours often shrink by half or more. In our test a flat-colour graphic fell from 8.6 KB to 2.9 KB. Photographs saved as PNG shrink less; the PNG to JPG Converter Online is much smaller for those.
Photographs and images with many gradients have lots of unique colours. Reduce the colours further, set a maximum width, or convert to WebP or JPG.
Lossy reduces the number of colours to save space; lossless keeps all colours and only repacks the data. Lossy gives the larger saving.
WebP and AVIF support transparency with smaller files. See the PNG to WebP Converter Online and the PNG to AVIF Converter Online.
Yes. It is free, needs no sign-up, adds no watermark and has no daily limit. It is provided by Websolindia.
No. Your images are read and processed inside your browser on your own device. They are never sent to Websolindia or anyone else, which is why the tool is safe for private photos.
No. New files are created from the pixels, so camera details, GPS location and other embedded metadata are not copied. Keep your originals if you need that information.
Up to 30 images per batch and 150 MB per image. Images above roughly 120 megapixels are declined with a clear message rather than freezing your browser.
Current versions of Chrome, Edge, Firefox and Safari on computers, phones and tablets. Large images and AI or AVIF features run faster on a computer.
Websolindia built it. We are a New Delhi website design, SEO and digital marketing company serving businesses since 2014. See our website designing and SEO services.
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