Developer Tools — Free Online Utilities
Developer tools for everyday coding: format and validate JSON, YAML and SQL, encode and decode data, minify code, and convert between formats. Everything runs in your browser, so your code and data never leave your machine.
Convert CSV/TSV data into beautifully formatted ASCII or Markdown tables.
Generate barcodes in Code 128, Code 39, EAN-13, UPC-A, and ITF-14 formats and download as SVG or PNG.
Encode or decode Base64 strings — works for text and files.
Convert numbers between binary, hexadecimal, octal, and decimal bases instantly.
Convert plain text to binary, hexadecimal, octal, or decimal — and back — with a per-character breakdown.
Generate a custom CSS reset stylesheet with preset options.
Calculate and compare CSS selector specificity (A, B, C).
Convert CSS properties to the nearest Tailwind CSS classes
Convert CSV data to JSON and JSON arrays back to CSV — with delimiter options and live preview.
Format and beautify code across multiple languages with configurable indentation.
Measure lines of code, cyclomatic complexity, nesting depth, and maintainability
Side-by-side code diff with syntax highlighting and patch export
Count total, blank, comment, and code lines in any pasted code with language auto-detection.
Convert code snippets to beautiful shareable PNG images.
Convert colors between HEX, RGB, HSL, HSV, and CMYK — with live preview.
Generate harmonious color palettes — complementary, triadic, analogous, and split-complementary — from any base color.
Parse and explain cron expressions in plain English — see the next 10 scheduled run times.
Convert any date string between ISO 8601, Unix timestamp, RFC 2822, and 10+ other formats.
Generate favicon files in multiple sizes from text or an uploaded image using Canvas API. Download individual PNGs or a ZIP with all sizes and ready-to-use HTML link tags.
Convert between file size units — bits, bytes, KB, MB, GB, TB, PB — in decimal (SI) and binary (IEC) modes.
Identify any file's true type by reading its magic bytes — no upload required.
Interactive reference of 80+ essential Git commands, organized by category with search and favorites.
Generate conventional commit messages following the Conventional Commits spec with type, scope, emoji prefix, breaking change flags, and issue references.
Minify HTML, CSS, and JavaScript to reduce file size — runs entirely in your browser.
Generate a complete, customisable HTML starter template in seconds.
Searchable reference of HTML entities with named, numeric, and hex forms — click to copy.
Encode special characters to HTML entities and decode entities back to plain text — supports named and numeric entities.
Live HTML, CSS, and JS editor with instant preview
Build HTML tables visually with cell editing, merging, and styling options.
Convert HTML to clean Markdown with support for tables, code blocks, and nested elements.
Complete reference of all standard HTTP status codes with descriptions and examples.
Generate SHA-1, SHA-256, SHA-384, and SHA-512 hashes from text or files — runs offline in your browser.
Enter an IPv4 address with a CIDR prefix or subnet mask to calculate network address, broadcast, host range, wildcard, and binary breakdown.
Look up the country, city, ISP, timezone, and map location of any IP address instantly.
Divide an IPv4 network into equal subnets or use VLSM to allocate subnets by host requirement.
Convert any image file to a Base64-encoded data URI string.
Paste CSV data to get a sortable, filterable, paginated data table
Side-by-side Markdown syntax and rendered output with a live playground.
Format, validate, and explore JSON with syntax highlighting, JSONPath browser, tree collapse, and schema inference.
Deep-compare two JSON objects and visualize added, removed, and changed keys.
Format, validate, and minify JSON — with syntax error pinpointing.
Format JSON with syntax highlighting or strip whitespace to minify — with real-time validation and size stats.
Generate JSON Schema (draft-07) automatically from a sample JSON object.
Validate JSON data against a JSON Schema with detailed path-level error messages.
Visualize JSON as an interactive collapsible tree with type highlighting.
Convert JSON to CSV and CSV to JSON with nested object flattening and smart type detection.
Convert JSON arrays into formatted HTML tables with sorting, zebra striping, and CSV export.
Convert JSON objects into TypeScript interface or type alias definitions automatically.
Convert JSON to well-formed XML with indentation, custom root element, and attribute mode.
Convert between JSON and YAML instantly in your browser.
Execute JSONPath expressions against JSON data to extract, filter, and explore nested structures.
Browse and explore the free JSONPlaceholder REST API interactively
Decode and inspect JWT tokens — header, payload, and signature — without any server round-trip.
Beautify, minify, and validate JavaScript and JSON code
Apply basic obfuscation transformations to JavaScript code: variable renaming, string encoding, and whitespace removal.
Run and test JavaScript code directly in your browser with console output.
Press any key to see its keyCode, key, code, charCode, and more.
Searchable keyboard shortcuts for Windows, macOS, VS Code, Chrome, Excel, Word, Figma, Photoshop, and Terminal.
Test every key on your keyboard with a visual QWERTY layout.
Generate Lorem Ipsum placeholder text by paragraph, sentence, word, or byte count — with HTML and plain text output.
Generate full HTML page templates with lorem ipsum for mockups and wireframes.
Convert Markdown to clean HTML with live preview, table of contents, and downloadable full-page output.
Generate SEO-optimized HTML meta tags with live Google and Twitter card preview.
Translate text to Morse code and Morse code back to text — with audio playback.
Measure your network latency and basic download speed using real HTTP requests.
Convert numbers between binary, octal, decimal, and hexadecimal — instantly with bitwise breakdown.
Convert numbers between any bases 2–36 with arbitrary precision, negatives, and floating point support.
Convert numbers to English words — up to trillions, with ordinal and currency formats.
Create strong, random passwords with customizable length and character sets — runs offline.
Generate placeholder image URLs and embed code using placeholder.com and Picsum.
Create custom QR codes for URLs, text, Wi-Fi, contacts and more — free, no signup.
Generate customizable QR codes for URLs, text, email, phone, SMS, WiFi, and vCard with color and size options.
Scan QR codes using your device camera or upload an image — decode any QR code in your browser.
Build and send HTTP requests directly from your browser with headers, body, and query params.
Roll dice, flip coins, draw random cards, and generate random numbers — all cryptographically random.
Interactive regular expression reference with live pattern testing and match highlighting.
Searchable library of 50+ common regular expression patterns with live tester.
Visual regex testing with color-highlighted matches and capture groups.
Generate regex patterns automatically from positive and negative example strings.
Test regular expressions with real-time match highlighting, capture groups, and replace mode.
Generate a robots.txt file with presets for common crawlers and custom user-agent rules.
Convert between Arabic numbers and Roman numerals — supports 1 to 3,999,999 with extended notation.
Convert between Roman numerals and decimals with vinculum support
Beautify and format messy SQL queries with proper indentation and keyword casing — instantly.
Visual SQL query builder for SELECT, INSERT, UPDATE, DELETE
Draw and edit SVG shapes in the browser
Combine multiple SVG icons into a single sprite file with usage snippets.
Display your screen resolution, viewport, device pixel ratio, browser details, hardware concurrency, and more.
On-screen pixel ruler with draggable guides and measurement pins for design work.
Hash strings with MD5, SHA-1, SHA-256, SHA-512, CRC32, and FNV-1a
Pad, trim, repeat, replace, wrap, escape, and extract substrings — all in one place.
Interactive searchable reference for 200+ Tailwind CSS v3 utility classes.
Convert CSV, TSV, or delimited text to HTML table, Markdown, or JSON
Convert any text into a clean, URL-friendly slug instantly.
Visualize text as colored bit patterns, toggle individual bits, and perform byte-level AND/OR/XOR/NOT operations.
Percent-encode or decode URLs and query parameters — full and component modes.
Break any URL into its components or assemble a URL from parts — with a live query-param editor.
Simulate URL shortening with localStorage-based link tracking.
Generate UUID v4, UUID v7, ULIDs, and Nano IDs — bulk generation with one click.
Convert any character or string between Unicode representations: U+ notation, decimal, hex, HTML entities, CSS content, URL encoding, UTF-8/UTF-16 bytes, and binary.
Convert between metric and imperial units — length, weight, temperature, area, volume.
Convert Unix timestamps to human-readable dates and back — supports seconds, milliseconds, and microseconds.
Build and send HTTP requests from your browser and inspect the response in detail.
Format, validate, and minify XML with syntax highlighting.
Validate YAML syntax and convert it to formatted JSON — entirely in your browser.
Build and generate cURL commands interactively
Convert cURL commands into JavaScript fetch(), Axios, or Python requests code.
Visually build <iframe> embed code with full control over size, sandbox policies, permissions, and loading strategy.