Image Compressor
Compress JPEG, PNG, and WebP images locally to reduce file size. Features real-time byte measurement, visual preview, and smart bypass protection.
Best solution
Local processing: Image Compressor; Reports exact byte reduction; preserves original if candidate expands.
Choose a file to start. Nothing is uploaded.
Single still image. JPEG uses white behind transparency. Decoder notices
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Methodology & calculation rule
Adjustable DCT Quantization Matrix → In-Memory Byte Measurement → Smart Bypass Protection
Adjust quality slider to balance visual crispness against byte size. Transparency composites onto white.
All image processing executes client-side within your browser sandbox via HTML5 Canvas and WebAssembly. No photographs, bitmaps, or metadata are ever uploaded to remote servers.
Output files are generated in-memory as local object URLs. Files must be smaller than 20 MB and under 24 megapixels.
Real-World Context & Technical Standards
Discrete Cosine Transform (DCT) Optimization
JPEG compression discards high-frequency spatial frequencies that human visual perception is least sensitive to, dramatically reducing file size without noticeable perceptual degradation at quality 80+.
Retaining Original When Re-Encode Expands
If an already highly-compressed image re-encodes into a larger byte count under standard canvas parameters, the tool preserves the original file bytes rather than outputting an artificially inflated file.
Privacy & EXIF Sanitation
Encoding via browser canvas draws raw pixel data onto a fresh surface, automatically shedding GPS geolocation coordinates, camera serial numbers, and thumbnail bloat from the exported image.
Related conversions
| Tool | Type | Format |
|---|---|---|
| HEIC to JPG | Diagnostic | JPEG |
| HEIC to PNG | Diagnostic | PNG |
| WebP to PNG | Diagnostic | PNG |
| PNG to JPG | Diagnostic | JPEG |
| JPG to PNG | Diagnostic | PNG |
Frequently Asked Questions
Why did the tool report "Original kept"?
If your file was already heavily optimized, re-encoding could produce a larger file. The tool safely keeps your original.
Does compression remove camera metadata?
Yes. Drawing onto a fresh browser canvas strips redundant EXIF metadata, GPS tags, and device serial numbers.