Web tools
Inspect, preview, and audit websites.
Aspect Ratio Calculator
Lock in an aspect ratio and compute missing width or height — for video, images, or layouts.
Cache-Control Header Builder
Build HTTP Cache-Control headers with presets for static assets, APIs, and private responses.
Color Blindness Simulator
Preview an image or hex color through the four most common color-vision deficiencies.
Color Converter
Convert any color between HEX, RGB, HSL, HSV, and CMYK in one place.
Color Picker & Contrast Checker
Pick colors, convert between HEX/RGB/HSL, and check WCAG contrast.
Content Security Policy Builder
Compose a CSP header by picking sources per directive, with copy-ready HTTP header and meta-tag output.
CSS Border Radius Generator
Sculpt rounded corners with per-corner control, including elliptical and 'squircle' shapes.
CSS Box Shadow Generator
Build CSS box-shadow values with a live preview — stack multiple shadows for depth.
CSS Gradient Generator
Build linear, radial, and conic CSS gradients with a live preview and copy-ready output.
CSS Specificity Calculator
Score one or more CSS selectors and see which one wins the cascade.
CSS Unit Converter
Convert px ↔ rem ↔ em ↔ pt ↔ % with an adjustable base font size.
HTML & CSS Formatter / Minifier
Beautify or minify HTML and CSS — pretty-print messy markup, or shrink it for production.
HTML Entity Encoder / Decoder
Encode HTML special characters or decode named and numeric entities back to text.
HTML Table Generator
Paste CSV or TSV and get a clean HTML, Tailwind-styled HTML, or Markdown table.
HTTP Cookie Builder & Parser
Construct or decode Set-Cookie headers with SameSite, Secure, HttpOnly, and prefix validation.
HTTP Message Parser
Parse a header block, raw request, or raw response into structured JSON with smart Set-Cookie / Cache-Control / Content-Type breakdowns.
HTTP Status Code Reference
Searchable reference of every HTTP status code with descriptions and category.
MIME Type Reference
Searchable reference of common MIME types by extension and category.
Palette Generator from Image
Extract the dominant colors from any image — for design systems, moodboards, or theming.
Query Parameter Manager
Add, edit, remove, and reorder URL query parameters with a live preview.
Robots.txt Generator
Build a robots.txt for your site with a guided UI.
Sitemap Validator
Validate sitemap.xml against the protocol and inspect every URL inside.
Slug Generator
Turn any string into a clean, URL-safe slug with configurable separators and length.
SSL Certificate Decoder
Paste a PEM certificate and inspect its subject, issuer, validity, SANs, and fingerprints.
Tailwind Color Picker
Browse the Tailwind CSS color palette and copy any swatch's class name, hex, or RGB.
URL Encoder / Decoder
Percent-encode and decode URL components safely.
URL Parser
Break a URL into protocol, host, path, query parameters, and fragment.
User-Agent Parser
Decode any User-Agent into browser, OS, device, engine, and CPU fields.