Files & Networking
Image Compression Savings Calculator
Enter the original and compressed file sizes to see bytes saved, the percentage reduction and the compression ratio. Or estimate savings from a target quality level.
How compression savings are measured
Two numbers tell the story: the percentage reduction (how much smaller the file got) and the compression ratio (original ÷ compressed). A file that drops from 1 MB to 250 KB is a 75% reduction and a 4:1 ratio.
reduction % = (1 − compressed ÷ original) × 100
Choosing the right format
- WebP / AVIF — best for photos and most web images; large savings over JPEG/PNG.
- JPEG — fine for photos when WebP isn't supported.
- PNG — keep for graphics needing transparency or sharp edges.
- SVG — unbeatable for logos and icons (vector, scales free).
How to use this calculator
- Enter the original size.
- Enter the compressed size.
- Read bytes saved, % reduction and ratio.
See more files & networking tools.
Frequently asked questions
What is a good compression ratio?
For web images, a 60–80% size reduction (ratio 3:1 to 5:1) is common with modern formats like WebP or AVIF while keeping good quality.
How does this help my website?
Smaller images load faster, improve Core Web Vitals (LCP) and cut bandwidth costs. Multiply the saving per image by your monthly views to see total bandwidth saved.
What's a good compression ratio for web images?
A 60–80% size reduction (a 3:1 to 5:1 ratio) is typical with modern formats like WebP or AVIF while keeping good visual quality. Photos compress more than flat graphics.
How does this help site speed?
Smaller images load faster and improve Core Web Vitals — especially Largest Contentful Paint (LCP). Multiply the per-image saving by your monthly pageviews to estimate total bandwidth saved.