zippydevtoolsCompressors
PNG Compressor (browser)
Compress PNG files locally with safe lossless and more aggressive size-reduction modes.
- Local browser processing only: no file upload.
- No remote persistence for input or output files.
Processed locally; the file never leaves your device.
Drop a PNG here or choose it from your device
One file at a time, up to 25 MB.
Compress PNG files locally in the browser with safe and aggressive modes for screenshots, website images, and UI assets.
When to use
Use it before publishing PNGs in pages, documentation, repositories, or products where file size affects loading.
Input
Choose safe or aggressive mode, set quality when required, and select a PNG file within the supported limit.
Output
The output is an optimized PNG download with before/after size comparison in the rich interface.
- Select safe mode to preserve quality or aggressive mode to reduce more.
- Upload a PNG within the tool size limit.
- Compare size and visually review transparency, small text, and edges.
- Download the optimized file and test it in the context where it will be published.
- Website images: Reduce screenshots and PNG assets to lower page weight and improve loading experience.
- Documentation: Compress screenshots before adding them to README files, docs, tickets, or knowledge bases.
- Product assets: Optimize interface images while preserving transparency when the PNG uses alpha.
- Aggressive mode: It can introduce visual loss; compare the result before replacing the original.
- Large files: Very large PNGs consume memory and can take longer in the browser.
- Transparency: The flow preserves alpha, but always verify transparent assets before publishing.
- Real performance: Smaller files can improve loading, but Core Web Vitals depend on page context.
- PNG Compression Workflow Before Uploads
Use a practical PNG compression workflow for screenshots, docs, and landing pages while checking readability, transparency, and output size.
Lossless PNG compression
Input: Upload a PNG and choose safe mode
Output: Smaller PNG download with preserved transparency.
Is my PNG file uploaded to a server?
No. Compression runs locally in the browser using a Web Worker.
What is the difference between safe and aggressive mode?
Safe prioritizes visual preservation without loss; aggressive targets smaller size with possible minor loss.
Is quality required in aggressive mode?
Yes. Aggressive mode requires a quality value between 0 and 100.
Is there an upload size limit?
Yes. The current limit is 25 MB per PNG file.
Is PNG transparency preserved?
Yes. The workflow is designed to preserve transparency in the output file.
How do I use this tool safely?
Use the tool as a short workflow: review the expected input, run processing, and validate the output: Fields: Mode (select, required); Quality (aggressive mode) (number, optional). Example workflow: Upload a PNG and choose safe mode -> Smaller PNG download with preserved transparency.. Enter the requested input, run the tool, and review validation messages or warnings before copying the result.
Which inputs and outputs should I check?
Check this tool's input fields, examples, and output before using the result: Mode (select, required); Quality (aggressive mode) (number, optional). Use the fields, formats, and limits described in the tool interface; review the output before applying it to critical workflows.