Is PNG compression truly lossless?

Yes. OxiPNG optimization removes metadata and optimizes compression structures without changing any pixel values. The output is pixel-for-pixel identical to the input.

How much can PNG files be reduced?

Typically 20-70%. PNGs with large areas of solid color see the biggest reductions. Screenshots often compress by 50%+.

Does it preserve transparency?

Yes, completely. Transparency (alpha channel) is fully preserved throughout the optimization process.

OxiPNG is a high-performance lossless PNG optimizer written in Rust. It applies multiple optimization strategies including better compression filters and palette optimization to minimize file size.

Can it handle large PNG files?

Yes. Since processing is local, there's no server file size limit. You can optimize large PNGs without any issues.

Should I use PNG or WebP?

PNG is ideal for images requiring transparency or lossless quality (logos, screenshots, graphics). For photos where transparency isn't needed, JPG or WebP are smaller.

Does it remove EXIF data?

Yes, by default. Removing metadata reduces file size further. The visual content is unchanged.

Compress PNG Online Free — Lossless, No Upload

Free Lossless Png Optimizer — No Limits, No Upload

Reduce PNG file sizes by up to 70% without changing a single pixel using OxiPNG optimization. imgavio processes everything locally in your browser using WebAssembly technology — your images never leave your device at any point. This gives you the privacy of desktop software with the convenience of an online tool.

100%

Client-side processing

Server uploads

∞

No limits ever

How to Use the imgavio Lossless Png Optimizer

1
Upload your images
Click the upload area or drag and drop your files. Supports PNG → APNG. You can select multiple files for batch processing.
2
Adjust settings (optional)
Use the quality slider and other controls to customize the output to your needs. The defaults are optimized for most use cases.
3
Download your results
Click download next to each file, or use "Download All" for batch downloads. Results are instant — no server round-trip required.

Frequently Asked Questions

Is PNG compression truly lossless?

Yes. OxiPNG optimization removes metadata and optimizes compression structures without changing any pixel values. The output is pixel-for-pixel identical to the input.
How much can PNG files be reduced?

Typically 20-70%. PNGs with large areas of solid color see the biggest reductions. Screenshots often compress by 50%+.
Does it preserve transparency?

Yes, completely. Transparency (alpha channel) is fully preserved throughout the optimization process.
What is OxiPNG?

OxiPNG is a high-performance lossless PNG optimizer written in Rust. It applies multiple optimization strategies including better compression filters and palette optimization to minimize file size.
Can it handle large PNG files?

Yes. Since processing is local, there's no server file size limit. You can optimize large PNGs without any issues.
Should I use PNG or WebP?

PNG is ideal for images requiring transparency or lossless quality (logos, screenshots, graphics). For photos where transparency isn't needed, JPG or WebP are smaller.
Does it remove EXIF data?

Yes, by default. Removing metadata reduces file size further. The visual content is unchanged.