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.

Generate a CSS linear gradient from two colors and an angle.

Generate CSS box-shadow values from simple inputs.

Generate CSS border-radius shorthand from one or more corner values.

Generate a CSS filter string from common values.

Generate basic JSON-LD WebApplication markup.

Generate FAQPage JSON-LD from question and answer pairs.

Generate BreadcrumbList JSON-LD from label and URL pairs.

Generate a canonical link tag to tell search engines your page's preferred URL.

Generate robots meta tags for index/follow options.

Convert .env key-value lines into a JSON object for configs and scripts.

Escape text into a valid JSON string value, handling quotes and control characters.

Convert basic Markdown headings, bold text, links, and paragraphs to HTML.

Extract one CSV column by its header name, one value per line.

Format simple SQL with line breaks before common clauses.

Convert labels into uppercase environment variable names.

Generate a Basic Authorization header from username and password.

Convert a simple curl GET command into a JavaScript fetch snippet.

Generate common HTML link tags for stylesheet, preload, canonical, and icons.

Generate a mailto link with subject and body.

Generate a WhatsApp click-to-chat link that opens a pre-filled message.

Remove UTM and common tracking parameters from URLs.

Convert an IPv4 address to decimal and binary.

Calculate usable IPv4 host counts from CIDR prefix length.

Estimate IPv4 network range from address and CIDR prefix.

Convert multiple Unix timestamps to ISO dates.

Convert a line-separated list into a JSON array.

Convert a JSON array into one item per line.

Count word frequency in pasted text and rank the most common words.

Count character frequency in pasted text.

Replace all exact matches in a text block locally.

Convert text to 8-bit binary byte values.

Convert 8-bit binary byte values back to text.

Encode or decode text with the ROT13 letter substitution.

Shift letters by a custom Caesar cipher amount.

Convert comma-separated values to tab-separated values.

Convert tab-separated values to comma-separated values.

Convert CSV rows into an HTML table snippet.

Convert label and URL lines into Markdown links.

Generate basic CORS headers for a known allowed origin.

Generate a tiny starter DNS zone file from a domain and IPv4 address.

Generate a practical .gitignore snippet for Node, macOS, logs, and Cloudflare projects.

Generate a compact .dockerignore starter file.

Escape special characters so text can be used literally in a regular expression.

Add sequential line numbers to pasted text for reference or debugging.

Collapse line breaks and extra whitespace in pasted text into clean single spaces.

Reverse the character order of any text, locally in your browser.

Find items in the first list that are missing from the second list.

Find items that appear in both of two pasted lists.

Merge two pasted lists into one, removing duplicate entries.

Find words that repeat more than once in a block of pasted text.

Extract all unique object keys from JSON.

Flatten nested JSON into flat dot-path keys for easier diffing or export.

Encode or decode Base64URL strings locally.

Convert text to hexadecimal character codes.

Convert hexadecimal character codes back to text.

Extract all http/https URLs found in a block of pasted text.

Extract email addresses from pasted text.

Remove HTML tags and keep readable text.

Search common DNS record types and what they are used for.

Search common HTTP request and response headers.

Search common HTML entities and characters.

Search useful CSS named colors and hex values.

Search common keyboard keys and browser key values.

Search common Unicode symbols for writing and UI work.

Search common network port numbers and services.

Search common HTTP request methods and uses.

Search common Markdown syntax patterns for headings, links, lists, and more.

Search common regular expression tokens.

Calculate cache hit rate from hits and misses.

Calculate service uptime from downtime minutes in a period.

Calculate allowed downtime from an uptime SLA and period length.