Dev utilities · 8 tools
Developer utilities
The 8 utility tools you hit daily during SEO implementation work: minifiers for shaving KB off pages (affects Core Web Vitals), encoders for special-character URLs, a JSON formatter for schema debugging, URL parsing, link extraction, WCAG contrast, and UTM builder.
Dev utilities
HTML Minifier
Strip whitespace & comments
Dev utilities
CSS Minifier
Remove whitespace & comments from CSS
Dev utilities
JSON Formatter
Format, validate & minify JSON
Dev utilities
Text Encoder / Decoder
Base64, URL, HTML entities, Hex
Dev utilities
URL Parser
Break down any URL
Dev utilities
Link Extractor
Pull URLs & emails from text
Dev utilities
Color Contrast Checker
WCAG AA/AAA ratio in real time
Dev utilities
UTM Link Builder
Campaign tracking URLs
About these tools
Dev utilities questions
- Does minifying HTML/CSS actually affect SEO?
- Yes indirectly via Core Web Vitals. Smaller file size = faster Time To First Byte (TTFB) and smaller Largest Contentful Paint resource (LCP). HTTP Archive 2024 median shows ~15KB HTML and ~60KB CSS per page. Minification typically saves 20-40% on both — 12KB off the critical path. Combined with Brotli compression, the delta translates to ~50-150ms faster LCP on slow connections.
- What's the difference between URL encoding and Base64?
- URL encoding (percent-encoding, RFC 3986) converts special characters to %XX for safe transport in URLs: space→%20, &→%26, etc. Base64 encoding (RFC 4648) converts arbitrary binary data to 64 safe ASCII characters, inflating size by ~33%. Use URL encoding for query strings and paths; Base64 for embedding binary (images in CSS, JWT tokens, data URIs). Never use Base64 for text content that will be indexed — Google cannot read Base64-encoded text.
- What WCAG contrast ratio does Google use for Lighthouse?
- Lighthouse uses WCAG 2.1 AA thresholds: 4.5:1 for normal text (under 18pt or 14pt bold), 3:1 for large text (18pt+ or 14pt+ bold), 3:1 for UI components and graphical objects. Our Contrast Checker calculates both AA and AAA (7:1 / 4.5:1). Note: Lighthouse only flags body text issues; it misses button borders, form focus rings, and disabled-state contrast — audit those manually.
- What UTM parameters should I always set?
- Three required (Google Analytics won't track the campaign without them): utm_source, utm_medium, utm_campaign. Two optional but valuable: utm_content (A/B test variants), utm_term (paid-search keyword, mostly legacy). Format: all-lowercase, no spaces, hyphens for multi-word. Example: ?utm_source=twitter&utm_medium=social&utm_campaign=serpgem-launch-2026. Our UTM Link Builder validates naming conventions and produces shareable URLs.
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