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Audit your site's SEO
Flagship
0–100 score + prioritized fixes · no signup · free
Popular 6
JSON Prettify / Minify Format, validate, and minify JSON SEO Analyzer Full SEO audit: paste one URL for a 0–100 score and prioritized fixes across meta, content, links, images, structured data, social, and security headers Base64 Encode / Decode Encode and decode Base64 text and files Merge PDFs Combine multiple PDF files into one UUID Generator Generate v4 UUIDs in bulk with one-click copy Image Compressor Compress images with adjustable quality
Data Converters 19
CSV ↔ JSON Convert between CSV and JSON formats YAML ↔ JSON Bidirectional conversion between YAML and JSON TOML ↔ JSON Bidirectional conversion between TOML and JSON XML ↔ JSON Bidirectional conversion between XML and JSON JSON → TypeScript Types Generate TypeScript interfaces from JSON samples JSON → Zod Schema Generate Zod validation schemas from JSON samples JSON → Go Struct Generate Go structs with json tags from JSON JSON → Rust (Serde) Generate Rust serde structs from JSON JSON → Kotlin Data Class Generate Kotlin data classes from JSON JSON → C# Class Generate C# classes with System.Text.Json attributes from JSON JSON → Java Class Generate Java classes with Jackson annotations from JSON JSON → GraphQL Schema Generate GraphQL SDL types from JSON JSON Diff Compare two JSON objects structurally JSON → JSDoc Typedefs Generate JSDoc @typedef definitions from JSON CSV → SQL INSERT Convert CSV rows into SQL INSERT statements SQL Explainer Explain any SQL query in plain English, clause by clause JSON ↔ Query String Convert between URL query params and JSON objects JSON → CSV Convert a JSON array of objects into CSV JSON Schema Generator Generate JSON Schema from sample JSON data
Formatters 13
Markdown TOC Generator Generate a table of contents from Markdown headings JSON Prettify / Minify Format, validate, and minify JSON SQL Formatter Prettify SQL queries HTML Prettify / Minify Format or compress HTML CSS Prettify / Minify Format or compress CSS JavaScript Prettify / Minify Format or compress JavaScript XML Prettify / Minify Format or compress XML Markdown Preview Live side-by-side Markdown editor and rendered preview HTML Preview Paste raw HTML and see it rendered in a sandboxed iframe Markdown Table Generator Build GitHub-flavored Markdown tables in a visual grid Markdown → HTML Converter Convert Markdown to clean HTML with live preview Markdown → PDF Converter Convert Markdown to a styled PDF document with customizable options HTML → Markdown Convert HTML into clean, readable Markdown
Encoders & Decoders 13
Base64 Encode / Decode Encode and decode Base64 text and files URL Encode / Decode Encode and decode URI components JWT Decoder Decode JWT tokens and inspect header, payload, and expiration AES Encrypt / Decrypt Encrypt and decrypt text with AES-256-GCM and a password X.509 Certificate Decoder Decode and inspect X.509 PEM certificates Number Base Converter Convert between decimal, hex, binary, and octal Text ↔ Binary Convert text to binary and back Text ↔ Hex Convert text to hexadecimal and back Base32 Encode / Decode Encode and decode Base32 (RFC 4648) Base58 Encode / Decode Encode and decode Base58 (Bitcoin alphabet) Roman Numeral Converter Convert numbers to Roman numerals and back HTML Entity Encoder / Decoder Encode and decode HTML entities with named and numeric support JWT Generator Generate and sign JWT tokens with HMAC algorithms
Generators 21
ULID Generator Generate sortable unique identifiers (ULID) UUID Generator Generate v4 UUIDs in bulk with one-click copy BIP39 Mnemonic Generator Generate and validate BIP39 mnemonic seed phrases Barcode Generator Generate 1D barcodes (Code128, EAN, UPC, and more) Hash Generator Generate MD5, SHA-1, SHA-256, SHA-512 hashes HMAC Generator Generate HMAC digests with a secret key RSA / EC Key-Pair Generator Generate RSA or EC key pairs as PEM Placeholder Image Generator Generate colored placeholder images at custom dimensions QR Code Generator Generate QR codes from text or URLs WiFi QR Code Generator Generate a QR code to join a WiFi network Password Generator Generate secure random passwords with crypto API Lorem Ipsum Generator Generate placeholder text in paragraphs, sentences, or words Favicon Generator Upload an image and generate favicons with custom shape, border, and padding Crontab Builder Build cron expressions visually with dropdowns and presets Password Strength Analyzer Check password entropy, strength, and crack time Fake Data Generator Generate realistic fake/mock test data and export to JSON, CSV, or SQL Sample File Generator Generate real, valid sample/dummy files at an exact size API Key Generator Generate secure API keys and secrets in various formats bcrypt Hash & Verify Generate and verify bcrypt password hashes .htpasswd Generator Generate Apache .htpasswd entries with bcrypt or SHA TOTP Generator & Validator Generate and validate time-based one-time passcodes
Image Tools 16
Image Compressor Compress images with adjustable quality Image Format Converter Convert images between PNG, JPEG, and WebP Font Converter Convert fonts between TTF, OTF, WOFF, and WOFF2 Image Resizer Resize images with aspect ratio lock SVG to PNG Convert SVG to PNG at 1x, 2x, or 3x scale SVG Optimizer Optimize and minify SVG files Base64 ↔ Image Convert images to base64 data URLs and vice versa Image Metadata Viewer View dimensions, file size, and EXIF data Image Color Picker Upload an image and click to pick colors Bulk Image Processor Compress, resize, and convert multiple images at once Image Pipeline Chain resize, format, and compress operations on a single image PNG → ICO Convert an image into a multi-resolution .ico favicon Image Color Palette Upload an image and extract its dominant colors Code to Image Turn code snippets into beautiful images with gradient backgrounds SVG → React Component Convert SVG markup into React/JSX components App Store Screenshots Generate marketing-style App Store screenshots with device frames
PDF Tools 13
Merge PDFs Combine multiple PDF files into one Split PDF Split a PDF into multiple files Rotate PDF Pages Rotate pages in a PDF Sign PDF Add a signature to a PDF Reorder PDF Pages Rearrange pages in a PDF by dragging and dropping Remove PDF Pages Delete specific pages from a PDF Extract PDF Pages Extract specific pages from a PDF into a new file Images to PDF Convert images to a multi-page PDF document PDF to Images Convert PDF pages to PNG or JPEG images Add Page Numbers to PDF Add page numbers to every page of a PDF PDF Metadata Editor View and edit PDF metadata like title, author, and keywords PDF Pipeline Chain multiple PDF operations: remove, rotate, add page numbers PDF Compressor Reduce PDF file size in your browser — lossless or strong compression
Text Tools 20
NATO Phonetic Alphabet Spell text using the NATO phonetic alphabet Emoji Picker Search emoji by name and copy with one click ASCII Art Generator Turn text into FIGlet-style ASCII art Case Converter Convert text between camelCase, snake_case, kebab-case, and more Text Diff Compare two texts and see highlighted differences Regex Tester Test regular expressions with highlighted matches Word / Character Counter Live count of characters, words, sentences, and reading time Find & Replace Find and replace text with regex support String Escape / Unescape Escape and unescape strings for JSON, HTML, URL, and more Unicode Inspector Inspect code points and UTF-8 bytes of any text Line Sort / Deduplicate Sort lines alphabetically or numerically, remove duplicates Text to Slug Convert any text to a URL-friendly slug Fancy Text Generator Turn text into fancy Unicode styles — bold, italic, cursive, and more Upside-Down Text Flip your text upside down Mirror & Reverse Text Reverse text backwards or mirror it with flipped letters Zalgo / Glitch Text Generate glitchy, cursed Zalgo text Aesthetic Text Generator Make fullwidth and spaced-out aesthetic / vaporwave text Text Repeater Repeat any text N times with optional separators Invisible Character Copy invisible Unicode characters for blank messages and names Regex Library Curated library of common regex patterns with one-click copy
Color Tools 6
Color Converter Convert between hex, RGB, HSL, and OKLCH Color Palette Generator Generate harmonious color palettes from a base color Contrast Checker Check WCAG AA/AAA contrast ratios Gradient Generator Visual gradient builder with CSS output Theme Editor Generate custom shadcn/ui themes with OKLCH color variables Color Blindness Simulator Simulate how images and colors look with different types of color blindness
CSS Generators 7
Box-Shadow Generator Build CSS box-shadows visually with layered shadows cubic-bezier() Editor Drag a curve to build a CSS easing function CSS clamp() Calculator Generate fluid clamp() font sizes Border-Radius Generator Round corners visually and copy the CSS Flexbox & Grid Playground Build Flexbox and CSS Grid layouts visually Squircle Generator Generate iOS-style squircle (superellipse) shapes Glassmorphism & Neumorphism Generate glassmorphism and neumorphism CSS
Web Utilities 14
Timestamp Converter Convert between Unix timestamps and human-readable dates URL Parser Break a URL into its components HTTP Status Code Reference Searchable list of HTTP status codes Meta Tag Generator Generate HTML meta tags, Open Graph, and Twitter Card tags Cron Expression Parser Parse cron expressions into human-readable descriptions Epoch Batch Converter Convert a list of Unix timestamps to human-readable dates Timezone Converter Convert a date and time between time zones Duration Calculator Time and business days between two dates Date Format Converter Convert a date between ISO, Unix, RFC, and more Countdown Timer Live countdown to any future date OG / Social Card Preview Preview Open Graph and Twitter Card meta tags with live social previews CSP Header Builder Build Content Security Policy headers with a visual form Webhook Tester Send test POST requests to webhook endpoints and inspect responses HTTP Request Builder Send HTTP requests and inspect responses — a lightweight online API client
Developer Utilities 16
ASCII Table Searchable ASCII character code reference JSON Path Finder Paste JSON and explore all paths to values Chmod Calculator Visual permission calculator for Unix .gitignore Generator Select presets and generate a combined .gitignore Environment Variable Parser Parse .env files and convert between formats Tailwind → CSS Converter Paste Tailwind classes and see equivalent CSS Aspect Ratio Calculator Calculate dimensions from aspect ratios Bytes / Filesize Converter Convert between B, KB, MB, GB, TB Package.json Explorer Paste package.json to see a clean breakdown of dependencies and scripts SSH Key Generator Generate RSA SSH key pairs in your browser robots.txt Generator Build robots.txt files with user-agent rules and presets Docker Run → Compose Convert a docker run command to docker-compose.yaml Dependency Vulnerability Scanner Scan npm lockfiles for known vulnerabilities (CVEs) via the OSV database .htaccess Generator Build .htaccess files with redirects, security, caching, and more Email Normalizer Normalize emails and find duplicates .editorconfig Generator Generate an .editorconfig file from a form
Math & Units 3
Network Tools 9
Random Port Generator Generate random TCP/UDP port numbers IPv4 Subnet Calculator Calculate network, broadcast, host range, and mask from CIDR IP Range / CIDR Expander Expand a CIDR block or IP range into every address IPv6 Expander / Compressor Expand or compress IPv6 addresses MAC Address Generator Generate random MAC addresses in any format Well-Known Port Reference Search common TCP and UDP port numbers User-Agent Parser Parse a User-Agent into browser, OS, and device What Is My IP See your public IP address, location, and connection details DNS Lookup Look up DNS records for any domain (A, MX, TXT, NS, and more)
SEO Tools 13
SEO Analyzer Full SEO audit: paste one URL for a 0–100 score and prioritized fixes across meta, content, links, images, structured data, social, and security headers Meta Tag Analyzer Analyze any webpage's meta tags, Open Graph, and Twitter Card data Heading Structure Checker Check any page's heading hierarchy for SEO issues Link Analyzer Analyze all internal and external links on any webpage Image SEO Checker Check images on any webpage for missing alt text and SEO issues Structured Data Validator Validate JSON-LD structured data on any webpage Technology Detector Detect what technologies any website is built with Redirect Checker Follow the full redirect chain for any URL SEO Report Run a full SEO analysis on any URL — meta tags, headings, links, images, and structured data, all on one page HTTP Header Analyzer Analyze HTTP response headers and grade security headers Schema Markup Generator Generate JSON-LD structured data for any schema.org type Keyword Density Analyzer Analyze keyword and phrase frequency in any text Sitemap Generator Generate a valid XML sitemap from a list of URLs
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