100% Free In-browser Transparency preserved

Compress PNG Images Free

Reduce PNG file size while preserving transparency. Choose PNG (lossless) or WebP (smaller). All processing happens in your browser — your images never leave your device.

Drop PNG images here or click to browse

PNG • Transparency supported • Batch compress supported

Accepts: .PNG
Output: .PNG or .WEBP
75%
px
Lower quality = smaller file size. 75% is recommended for most photos.
Never uploaded·How to use this tool
0 files
Related tools: Compress Image Compress JPEG Compress WebP MB to KB Resize to 20KB

How it works

Compress PNG images in 3 steps

1

Upload your PNG

Drop your .png files onto the tool. Transparent PNGs are fully supported. Add multiple files for batch processing.

2

Choose output format

Keep as PNG for maximum compatibility, or choose WebP for even smaller file sizes while preserving transparency.

3

Download compressed

Download your compressed PNG or WebP files individually or all at once as a ZIP archive.

FAQ

Frequently asked questions

Yes. When the output format is PNG, full transparency (alpha channel) is preserved exactly. When you choose WebP as the output, transparency is also fully supported — WebP is one of the few formats that supports both lossy compression and alpha transparency simultaneously, often producing smaller files than PNG.

PNG uses lossless compression — every pixel is stored exactly. The quality slider has no effect on PNG output because lossless means no quality trade-off. WebP uses lossy compression controlled by the quality slider, which can produce files 25–50% smaller than PNG for the same perceived visual quality. Both formats support transparency. WebP is supported by all modern browsers.

No. All processing happens entirely in your browser using the HTML5 Canvas API. Your images never leave your device. This means instant results, complete privacy, and no file size restrictions from server-side limits.

PNG is already a losslessly compressed format. The browser's PNG encoder may not achieve the same compression ratios as dedicated tools like pngcrush or oxipng, which use more aggressive lossless algorithms. For much smaller file sizes, try switching the output to WebP — this will apply lossy compression and often reduces PNG files by 50–70%.

Yes. Select multiple PNG files at once or drag and drop a batch. All files are compressed with the same settings. When all files are done, a Download All (ZIP) button appears so you can grab everything in one click.

Everything you need to know about compressing PNG images

PNG (Portable Network Graphics) is the most widely used lossless image format on the web. It is the go-to format for logos, icons, screenshots, and any image that requires a transparent background. However, PNGs can be large — a full-screen screenshot can easily exceed 1–3MB — making compression essential for fast-loading websites.

Why compress PNG files?

Large PNG files significantly slow down web pages, increasing both load times and bandwidth costs. Compressing PNGs — particularly by converting them to WebP — can reduce file sizes by 30–70% without any visible quality loss. This directly improves Core Web Vitals scores, Lighthouse performance, and user experience.

PNG vs WebP: which should you use?

WebP was designed by Google as a modern replacement for PNG and JPEG. It supports both lossless and lossy compression as well as transparency, typically achieving 25–50% smaller files than PNG at equivalent quality. All modern browsers (Chrome, Firefox, Safari, Edge) support WebP. For the web, WebP is almost always the better choice. For applications that require maximum compatibility (desktop software, some email clients), PNG remains the safe option.

Does compressing PNG affect transparency?

No. Both PNG and WebP output formats fully support transparency. When you compress a PNG with transparency using this tool, the alpha channel is preserved exactly in the output file — whether you choose PNG or WebP as the output format. The transparent areas of your logo or icon will remain perfectly transparent.

Why use JustDownSize to compress PNG?

JustDownSize compresses PNG files entirely in your browser, with no server uploads and no account required. You get instant results, complete privacy, and the flexibility to output as PNG or WebP depending on your needs. The quality slider and max-width control give you precise control over the output file size.