Developer And SEO Tools

Convert a dotted-decimal subnet mask's total bit count to CIDR prefix notation.

Calculate the percentage of available bandwidth currently in use.

Calculate the maximum sustained requests per second allowed under a rate limit.

Calculate uptime percentage and allowed downtime from total time and downtime minutes.

Estimate page load time from total page weight and effective connection speed.

Estimate free-space signal path loss in dB from distance and frequency.

Convert a power ratio to decibels using the 10·log10 formula, useful for audio and RF work.

Convert up to 16 binary digits to their exact decimal equivalent.

Convert a safely representable non-negative decimal integer to its exact binary representation.

Calculate the number of usable host addresses for a given subnet mask CIDR prefix.

Format JSON, validate syntax, and make raw JSON easier to read.

Minify JSON by removing whitespace while preserving valid data.

Convert an array of JSON objects into CSV.

Convert CSV rows into JSON objects using the header row as keys, right in your browser.

Encode or decode Base64 text locally -- no data leaves your browser or gets uploaded.

Encode or decode URL components (percent-encoding) for query strings and paths.

Escape or unescape HTML entities for safe snippets.

Turn titles into clean, lowercase, hyphenated URL slugs safe for links and filenames.

Convert CSV-style text into a Markdown table.

Compare two blocks of text line by line.

Test a regular expression against sample text.

Generate a simple robots.txt file with a sitemap line.

Generate a small sitemap.xml from a list of URLs.

Preview a search title and meta description length.

Build tagged campaign URLs from UTM parameters.

Convert text between uppercase, lowercase, title case, sentence case, camelCase, and snake_case.

Count words, characters, sentences, and estimated reading time.

Sort lines alphabetically and remove blank lines if needed.

Clean repeated spaces, tabs, and line breaks.

Generate SHA-1, SHA-256, SHA-384, and SHA-512 hashes with Web Crypto.

Generate RFC 4122 version 4 UUID values locally, five at a time, no server round-trip.

Convert between Unix timestamps and human-readable dates.

Explain simple five-field cron expressions.

Validate a card or ID number locally using the Luhn checksum algorithm.

Check an IBAN's structure and mod-97 checksum locally.

Encode or decode Base32 (RFC 4648) text locally.

Encode or decode Base58 text locally, the alphabet used by Bitcoin addresses.

Strip blank lines and leading indentation from JavaScript locally -- a safe, whitespace-only minify that can't break your code.

Check a VIN's check digit, region, and model year locally using the standard formula.

Search common HTTP status codes and meanings.

Search common MIME types by extension or content type.

Check WCAG contrast ratio between two hex colors.

Build Open Graph and Twitter card meta tags from page details.

Generate hreflang tags from locale and URL pairs.

Generate common redirect rules for Cloudflare Pages, Netlify, and Apache.

Decode JWT header and payload locally without verification.

Minify simple HTML by collapsing whitespace between tags.

Minify simple CSS by stripping comments and extra whitespace.

Format simple XML markup with indentation.

Convert a number between bases from 2 to 36.

Convert binary numbers to decimal and hexadecimal.

Convert hexadecimal numbers to decimal and binary.

Convert text to ASCII codes or ASCII codes back to text.

Convert text to International Morse code.

Convert letters to the NATO phonetic alphabet.

Break a URL into protocol, host, path, query, and hash parts.

Parse query string parameters into readable key-value pairs.

Convert HEX color codes to RGB values for use in CSS, design tools, or code.

Convert RGB color values to a HEX color code for use in CSS or design tools.

Convert HSL color values to a HEX color code for use in CSS or design tools.