JPG (JPEG)
Best for: Photographs, images with gradients, web images
Our JPG compressor uses MozJPEG, an advanced JPEG encoder that produces files approximately 30% smaller than standard JPEG encoders at equivalent visual quality.
- Typical savings: 40-60% smaller than unoptimized JPGs
- Default quality: 85 (optimized for web use)
- Progressive encoding: Images load progressively in browsers
- Trellis quantization: Advanced optimization for smaller files
- Metadata: EXIF/XMP stripped by default for privacy
PNG
Best for: Screenshots, graphics with text, logos, images with transparency
Our PNG compressor uses smart lossy compression (the same technique as TinyPNG). We intelligently reduce your image to an optimized 256-color palette, achieving dramatic size reductions while keeping changes visually imperceptible.
- Typical savings: 30-70% smaller (especially for screenshots and graphics)
- Compression type: Smart lossy (palette optimization, like TinyPNG)
- Transparency: Fully preserved
- Auto-detection: Graphics get crisp edges, photos get smooth gradients
- Best gains: Screenshots, logos, UI graphics, icons
Note: Our PNG compression is not lossless. Like TinyPNG, we use intelligent quantization for maximum size reduction. For truly lossless PNG compression, use tools like oxipng or pngcrush (which typically achieve 5-15% reduction).
Universal Compressor (39 Input Formats)
Thanks to Convert.FAST technology, our Universal compressor accepts 39 image formats. We convert them to JPG or PNG, then apply our compression.
How it works:
- Drop any supported format (WebP, AVIF, HEIC, RAW, PSD, etc.)
- We detect if your image has transparency
- Transparent images become compressed PNG
- Opaque images become compressed JPG
Supported input formats:
- Modern web formats: WebP, AVIF
- Apple/Mobile: HEIC, HEIF
- Standard formats: BMP, GIF, TIFF, ICO
- Professional: PSD (Photoshop)
- RAW camera (26 formats): CR2, CR3, NEF, ARW, RAF, DNG, RW2, ORF, PEF, and more
Output Format Comparison
Compress.FAST outputs two formats: JPG and PNG. Here's when to use each:
| Format | Compression | Transparency | Best For |
|---|---|---|---|
| JPG | Lossy (MozJPEG) | No | Photos, web images |
| PNG | Smart lossy (palette) | Yes | Screenshots, graphics, logos |
Which Format Will I Get?
- Drop a JPG → Get a compressed JPG
- Drop a PNG → Get a compressed PNG
- Drop anything else (WebP, HEIC, RAW, etc.):
- Has transparency → Get a compressed PNG
- No transparency → Get a compressed JPG
Which Compressor Should I Use?
- For photos: Use the JPG Compressor
- For screenshots and graphics: Use the PNG Compressor
- For mixed batches or other formats: Use the Universal Compressor
- Need WebP or AVIF output? Use Convert.FAST for format conversion