Free tools for web & seo calculations and conversions. All tools run in your browser with no data sent to any server.
All Web & SEO Tools
UTM Link Builder
Build URLs with UTM tracking parameters
User-Agent Parser
Parse a user-agent string for quick details
URL Parser
Parse a URL into protocol, host, path, and query
Sitemap XML Generator
Generate a simple sitemap.xml from a list of URLs
Robots.txt Generator
Generate a robots.txt file with common rules
Meta Tag Generator
Generate common SEO meta tags for a page
SERP Preview Tool
Preview how your page appears in Google search results
HTTP Header Viewer
Paste and parse HTTP headers for inspection
CSS Unit Converter
Convert between px, rem, em, percent, vw, and vh
Color Contrast Checker
Check contrast ratio between two colors
Color Blindness Simulator
Simulate how images appear to people with color vision deficiency
Open Graph Preview
Preview how links appear on social media
Typography Scale Generator
Generate harmonious type scales with modular ratios
CSS Minifier
Minify CSS by removing comments and whitespace for smaller file sizes
Spacing System Calculator
Generate design system spacing scales with visual preview and export options
Hreflang Tag Generator
Generate hreflang link tags for multilingual SEO in HTML, XML sitemap, and HTTP header formats
Meta Title Description Length Checker
Check meta title and description length with live Google SERP preview
Robots.txt Tester
Test and validate robots.txt files with URL path checking