Image Compression BenchmarkCompare JPEG, WebP, AVIF & PNG
Upload any image and instantly see file size vs quality tradeoffs across all major formats and compression levels. SSIM scores show exactly how much quality you lose at each setting.
Upload an image to benchmark
Drag & drop or click — JPEG, PNG, WebP, AVIF supported
Larger images take longer to process
How It Works
Upload Your Image
Drop any JPEG, PNG, WebP, or AVIF image. No account, no upload limits — everything runs locally in your browser.
Benchmark Runs Automatically
Your image is compressed to 16 variants across JPEG, WebP, AVIF, and PNG at quality levels 90, 75, 60, and 40. SSIM scores are computed for each to measure quality loss.
Compare & Choose
Click any variant to compare it side-by-side with the original using a drag slider. Download the best result or go straight to the converter.
Which Image Format Is Best for the Web?
Choosing the right image format can cut file sizes by 30–70% without any visible quality loss. WebP consistently outperforms JPEG at equivalent visual quality, while AVIF goes even further — delivering JPEG-level quality at roughly half the file size.
SSIM (Structural Similarity Index) is the standard metric for measuring perceptual image quality. A score of 1.0 means pixel-perfect reproduction. Most web images are acceptable above 0.92, excellent above 0.97. This benchmark lets you see exactly where each format falls at every compression level.
PNG remains useful for images with hard edges, flat colors, or transparency, where its lossless compression preserves quality that JPEG would degrade. For photographic content, WebP at quality 80 is the current best practice for web delivery.
Image Format & Compression — FAQ
Common questions about choosing the right image format
What is SSIM and what score should I aim for?
SSIM (Structural Similarity Index Measure) quantifies perceptual image quality on a scale from 0 to 1, where 1 means identical to the original. For web images, 0.95+ is excellent and virtually indistinguishable from the original. 0.90–0.95 is good for most uses. Below 0.85 may show visible artifacts on close inspection.
Is WebP always better than JPEG?
WebP is generally 25–35% smaller than JPEG at equivalent visual quality. However, browser and platform support matters — all modern browsers support WebP, but some older systems and email clients do not. For new web projects, WebP is the recommended default for photographic content.
When should I use AVIF instead of WebP?
AVIF typically achieves the same visual quality as WebP at 20–30% smaller file sizes. However, AVIF encoding is slower, and support is slightly less universal (though all major browsers support it as of 2024). Use AVIF when maximum compression matters and you control the delivery environment.
Why is PNG always the largest file in this benchmark?
PNG is a lossless format — it preserves every pixel exactly. The 'quality' levels in PNG control compression speed, not visual quality. PNG excels for images with text, line art, or transparency, where JPEG compression would create visible artifacts.
What quality level should I use for web images?
Quality 75–80 is the standard recommendation for photographic web content. At this level, JPEG files are 50–70% smaller than the original with no visible quality loss at normal viewing sizes. WebP at 75 quality is typically 25–35% smaller than JPEG at 80 with the same visual quality.
Can I use the compressed image directly from this tool?
Yes — click the download button on any variant card to save that compressed image. Alternatively, use the format-specific tools linked on each card for batch processing, additional controls, and format conversion.
Ready to Convert or Compress?
Use these tools to apply your chosen format at scale