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Compress an image online without visible quality loss

Reduce the size of your JPEG, PNG and WebP images online for free. Web and SEO optimization.

Published on January 10, 2026

Heavy images slow down your website, degrade your Google PageSpeed score and increase your bounce rate. Compressing images is one of the most impactful optimizations for web performance — and it can be done online, without software.

Understanding the conversion

Image compression can be lossy or lossless. Lossy compression (JPEG, lossy WebP) reduces quality imperceptibly to the eye to achieve 40–80% reductions. Lossless compression (PNG, lossless WebP) optimizes encoding without removing information — 10–30% reduction. WebP offers an average 25–35% additional gain over JPEG at equivalent quality. AVIF offers even more compression but browser support is more recent.

📐 Formula

Compression ratio = Original size / Compressed size | Savings % = (1 - Compressed size / Original size) × 100

📊 Conversion table

Format Compression type Typical savings Transparency Recommended for
JPEG → JPEG opt. Lossy 20–60 % No Photos
PNG → PNG opt. Lossless 10–30 % Yes Logos, icons
JPEG → WebP Lossy 25–35 % Yes Modern web
PNG → WebP Lossy/Lossless 26 % Yes Universal replacement
Any → AVIF Lossy 40–50 % vs JPEG Yes Recent browsers

💡 Practical examples

Example 1: heavy e-commerce product photo

4MB photo (camera JPEG) → compressed to 150KB (80% quality). Savings: -96%. Result: 26× faster loading, visually identical quality at standard display size.

Example 2: optimize landing page images

Before: 3 images at 800KB each = 2.4MB. After WebP compression: 3 × 120KB = 360KB. 2MB gain on the page. Direct impact on Google's LCP (Largest Contentful Paint).

Example 3: PNG logo with transparency

A 500KB PNG logo can be losslessly compressed to 120KB with ToolSmartly. No degradation of transparency or edges.

⚡ Use the tool

Try our free online tool — no installation required.

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