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Optimization Benchmarks Reference
- JavaScript (initial load): under 200 KB minified+gzipped
- CSS: under 50 KB minified+gzipped
- Images: under 100 KB per image for content images
- Hero images: under 200 KB (WebP preferred)
- Total page weight: under 1.6 MB (Google recommendation)
- Web fonts: under 100 KB per font family (WOFF2)
The File Size Analyzer on TechConverter.me gives you actionable insights into file sizes, compression potential, and performance impact — helping you make informed optimization decisions for web performance and storage management.
Examples
Example 1: Analyzing a JavaScript Bundle
File: main.bundle.js
Raw size: 487 KB
Minified size: 312 KB (36% reduction)
Gzip compressed: 89 KB (72% reduction from minified)
Brotli compressed: 74 KB (76% reduction from minified)
Performance benchmark:
⚠ 312 KB minified exceeds recommended 200 KB initial JS budget
✓ 89 KB gzipped is within acceptable range for most connections
Load time estimates (gzipped):
Slow 3G (1 Mbps): 0.7 seconds
Fast 3G (10 Mbps): 0.07 seconds
4G LTE (50 Mbps): 0.014 seconds
WiFi (100 Mbps): 0.007 seconds
Optimization suggestions:
- Consider code splitting to reduce initial bundle size
- Enable tree shaking to remove unused exports
- Check for duplicate dependencies with bundle analyzer
Example 2: Analyzing an Image
File: hero-banner.jpg
Raw size: 2.4 MB
Dimensions: 3840 × 2160 pixels (4K)
Color depth: 24-bit (16.7 million colors)
Transparency: No
Performance benchmark:
⚠ 2.4 MB is too large for a web hero image
Recommended: under 200 KB for hero images
Optimization opportunities:
Resize to 1920×1080: ~600 KB (75% reduction)
Convert to WebP: ~180 KB (92% reduction from original)
Compress JPEG (80%): ~320 KB (87% reduction)
Recommended action: resize to 1920×1080 and convert to WebP
Estimated final size: 150-200 KB
Example 3: Analyzing a CSS File
File: styles.css
Raw size: 156 KB
Minified size: 98 KB (37% reduction)
Gzip compressed: 18 KB (82% reduction from minified)
Performance benchmark:
✓ 98 KB minified is within the 50-100 KB recommended range
✓ 18 KB gzipped is excellent
Optimization suggestions:
- Remove unused CSS rules (estimated 30-40% of rules may be unused)
- Consider critical CSS extraction for above-the-fold content
- Split into component-specific files for better caching