Transparency-aware
Alpha data is retained when PNG remains the output, avoiding the accidental solid background common in JPEG-only workflows.
Compress PNG Images Online
Optimize PNG images locally with lossless compression while preserving dimensions and transparency.
Local processingBatch readyIndividual or ZIP download
Settings
Upload and compress images
Drop or paste images here
PNG only. Add one file or a whole batch.
- PNG
Local files never leave your device.
Optimize PNG structure without inventing a quality slider.
The default PNG path removes avoidable encoding overhead without deliberately changing decoded pixels. Transparency and dimensions remain intact unless you choose a conversion or resize.
- Input
- PNG
- Default output
- Losslessly optimized PNG
- Transparency
- Preserved on the PNG path
Honest about hard files
The page does not promise that every already-optimized PNG will shrink. Results show growth as well as savings so you can reject an unhelpful output.
How it works
PNG pixels and filenames stay in the browser. The lossless optimizer is loaded only when needed and runs in a dedicated worker.
Choose PNG images
Add PNG files. This route accepts PNG content only and verifies the signature rather than trusting the filename.
Keep or convert
Keep the original format for lossless optimization, or deliberately choose WebP, AVIF or JPEG when conversion suits the image.
Check actual savings
The worker optimizes each file and reports whether it became smaller. Download only the results you want to keep.
Useful for
- Reduce transparent logos, UI captures and interface assets.
- Optimize a batch of PNG exports before committing them to a repository.
- Compare lossless PNG against a transparent WebP or AVIF conversion.
Questions about compress png images online
Is PNG compression lossless?
Keeping PNG as the output uses a lossless PNG optimizer, so decoded pixels and transparency are preserved. Converting to another format follows that format's behavior.
When should I keep the PNG format?
PNG is often appropriate for transparency, interface graphics and artwork with sharp edges. Photographs may be smaller as WebP, AVIF or JPEG, depending on the visual result you accept.
Can I lower PNG quality?
Not on the lossless PNG path. Quality controls are hidden when they would be misleading. You can choose another output format if you need lossy compression.