Lossy Compression vs Lossless Compression
Differences, use cases, and when to use each
Lossy compression permanently removes data to achieve smaller files (JPEG, WebP lossy). Lossless compression reduces size without losing any data, allowing perfect reconstruction (PNG, WebP lossless). The choice is between file size and perfect fidelity.
Quick Comparison
| Feature | Lossy Compression | Lossless Compression |
|---|---|---|
| Data Loss | Irreversible data removal | No data loss (reversible) |
| File Size | Smaller (more aggressive) | Larger than lossy |
| Quality | Degraded by repeated saves | Perfect at any save count |
| Formats | JPEG, WebP (lossy), AVIF | PNG, WebP (lossless), GIF |
| Best For | Photographs, final web delivery | Screenshots, source files, text images |
When to Use Each
When to Use Lossy Compression
Use lossy compression for photographic content delivered on the web where smaller file sizes outweigh minor quality reduction. JPEG and lossy WebP are ideal for photos.
When to Use Lossless Compression
Use lossless compression for screenshots, diagrams, source assets, and any image with sharp edges or text where quality artifacts would be noticeable.
Pros & Cons
Lossy Compression
Lossless Compression
Verdict
Lossy for final web delivery of photographs. Lossless for source files, screenshots, and any image where artifacts would be visually unacceptable. Never use lossy as your source archive format.