Compress PNG Online
Compress PNG images online without unnecessary quality loss.
Reduce PNG file size while preserving image quality and transparency where possible. Upload one or multiple PNG images and download the optimized files.
Upload PNG Images
Drag & drop PNG images here · Choose PNG Images
PNG • Single & Multiple Images Supported
🔒 100% In-Browser Privacy: Your PNG files are processed locally in your web browser. No image data or pixels are ever uploaded to any external server.
What Is PNG Compression?
How lossless Deflate streams and adaptive filtering reduce PNG file sizes.
PNG evaluates 5 different predictive filters (None, Sub, Up, Average, Paeth) for every image row to minimize byte entropy before compression.
Applies LZ77 sliding-window compression paired with Huffman entropy coding to drastically shrink repeated byte sequences without altering image data.
Preserves 8-bit alpha channels in tRNS or RGBA chunks while safely discarding bloated camera headers (tEXt, zTXt, iTXt, eXIf).
How to Compress PNG Online
Follow these 6 simple steps to optimize your PNG files.
Drag and drop one or multiple PNG graphics, screenshots, or transparent logos.
Select Lossless (0% pixel change), Balanced (Recommended), or Maximum compression.
Fine-tune color depth quantization or specify target file-size limits if needed.
Our in-browser engine applies scanline filters and Deflate optimization in milliseconds.
Use the interactive split divider to verify crystal-clear clarity and transparency.
Save your compressed PNG or download a bundled ZIP with zero waiting.
PNG Compression Use Cases
Optimize graphic assets for speed, quality, and bandwidth efficiency.
Maintain crisp edges and transparent alpha channels for app icons, navigation logos, and design system components.
Screenshots contain large solid color blocks that compress exceptionally well under indexed palette optimization.
Smaller PNG payloads improve Google Core Web Vitals (LCP) and provide instantaneous mobile page loading.
PNG Compression vs. Resizing
Understanding the difference between reducing file bytes and altering pixel grids.
Compression optimizes entropy coding and reduces redundant color indexing without changing pixel width and height (e.g. 2400×1600 px graphic goes from 2.8 MB to 1.7 MB).
Resizing changes the physical pixel grid dimensions (e.g. from 2400×1600 px down to 1200×800 px). If you need exact pixel dimensions for website banners or icons, visit our dedicated Resize Image Tool.
Frequently Asked Questions
Everything you need to know about compressing PNG images online.
Upload your PNG image into our png compressor, choose your desired optimization level (Lossless or Balanced), configure optional palette settings, click 'Compress PNG', and download your compressed PNG image instantly.
In Lossless mode, decoded pixel data is 100% untouched and mathematically identical. In Balanced or Maximum mode, palette quantization optimizes the color depth to reduce png size while preserving clean graphic edges and transparency.
Lossless PNG compression optimizes Deflate streams, evaluates 5 adaptive scanline filters (None, Sub, Up, Average, Paeth), and strips non-essential metadata chunks without modifying a single pixel value.
Yes. Transparency is strictly preserved across all compression modes. The alpha channel (both full and partial transparency) remains intact and is never flattened against white.
Yes. You can upload and compress multiple PNG images in one session, download them individually, or download all completed files in a single ZIP archive.
No. By default, original pixel width and height are preserved. You can optionally enable Custom Dimension Scaling if you wish to resize the image.
If a PNG is already optimally compressed, re-encoding cannot reduce it further. ReducerImage accurately detects this and shows that no further reduction was achieved instead of faking savings.
Yes. When 'Remove unnecessary metadata' is enabled, ancillary chunks such as tEXt, zTXt, iTXt, pHYs, and eXIf are stripped to minimize file size and enhance privacy.
Yes. PNG natively supports full and semi-transparent alpha channels, whereas standard JPG does not support transparency at all.
Yes. ReducerImage is 100% mobile-friendly and responsive on iPhone, iPad, Android, and tablets with touch drag-and-drop and instant downloads.
Our online png compressor processes large PNGs using memory-efficient buffers. Files up to 50 MB are supported safely inside modern web browsers.
No. All PNG parsing, decoding, filtering, and Deflate compression happen 100% locally in your web browser. As a completely free tool, your images never leave your device.
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