Free · In-Browser · No Upload
Optimize PNG Online
Make PNG files dramatically smaller with smart colour quantization — the same technique used by popular PNG optimizers — while keeping full transparency.
- No upload — 100% private
- Instant, in-memory processing
- Free, no sign-up, no watermark
Step by step
How to use Optimize PNG
- 01
Step 1
Add PNG files
Drop in one or many PNG images, or click to browse.
- 02
Step 2
Choose a colour level
Pick lossless re-packing or reduce to 256, 128 or 64 colours for maximum savings.
- 03
Step 3
Download
See the savings for each file and download individually or as a ZIP.
Help & clarification
Frequently Asked Questions
How does PNG optimization work?
PNG files store every colour exactly. Most images look identical with a palette of 256 colours or fewer, so reducing the palette — with dithering-free smart quantization — often cuts file size by 50–80% while keeping transparency.
Is the optimized PNG still lossless?
The “Lossless” option is pixel-perfect. The colour-reduction options are visually near-identical for graphics, logos and screenshots, but are technically lossy.
Does it keep my file format?
Yes. Your images stay PNG — only the file size changes.
Are my images uploaded to a server?
No. Every operation runs locally in your browser using the HTML5 Canvas engine. Your files never leave your device, so they stay completely private.
Is this tool free to use?
Yes — it's completely free with no sign-up, no watermarks added to your output and no daily limits.
Keep creating
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