Developer Tools

HTML Editor (WYSIWYG) — A simple in-browser WYSIWYG editor — format with the toolbar, paste rich text from Word or web pages, and copy the resulting HTML.

JSON Formatter / Validator — Format, minify, or validate any JSON in your browser. Choose indent style and see error details for invalid input.

Markdown to HTML — Convert Markdown to HTML with live side-by-side preview. Supports headings, lists, links, images, code blocks, blockquotes, and empha...

Text Diff / Compare — Compare two blocks of text and see exactly what changed — added lines in green, deleted in red, unchanged in gray.

JWT Decoder — Paste a JWT and see the header, payload, expiry, and signature parts decoded. Everything happens in your browser.

CSV ↔ JSON — Convert tabular data between CSV and JSON. Header row detection, custom delimiter, quoted-field-with-comma support.

Regex Tester — Test JavaScript regular expressions live — see matches highlighted in your text and captured groups in a list.

Color Converter — Convert between HEX, RGB, HSL, and RGBA — pick a color or type any format and the others update live.

Number Base Converter — Convert numbers between decimal, hex, binary, octal — or any arbitrary base from 2 to 36.

JSON Diff — Compare two JSON values structurally — see exactly what was added, removed, or changed, with full key paths.

Cron Expression Builder — Edit a 5-field cron expression and see plain-English description plus the next 5 fire times in your local timezone.

Meta Tag Generator — Generate SEO meta tags, Open Graph tags, and Twitter Card tags for any page — with a live Google search-result preview and length w...

Color Palette Generator — Pick a base color and generate a harmony palette — complementary, analogous, triadic, tetradic, split-complementary, monochrom...

CSS Gradient Generator — Build linear, radial, or conic CSS gradients visually. Add unlimited color stops, drag the angle, see the live preview, and cop...

Box Shadow Generator — Build CSS box-shadow visually — tune offset, blur, spread, color, opacity, and inset with live preview.

Markdown Table Generator — Build Markdown tables with a visual cell editor — set rows/columns, click to edit any cell, pick alignment, or import from CSV.

Color Contrast Checker — Pick a foreground and background color and instantly see the WCAG 2.1 contrast ratio with pass/fail badges for AA and AAA, norm...

SQL Formatter — Paste any SQL query and get it formatted with proper indentation, keyword casing, and clause breaks. Supports 10 dialects including Post...

YAML Formatter — Paste any YAML and format it cleanly — pick indent width and line wrap, optionally sort keys. Also validates YAML syntax and converts b...

JSON to TypeScript — Paste a JSON payload and instantly get TypeScript interfaces (or type aliases) describing its shape. Optionally mark all properties...

Cron Visualizer — Paste any 5-field cron expression and instantly see: a plain-English description, a field-by-field breakdown, and the next 10 schedule...

GitHub Badge Maker — Generate Shields.io-style SVG badges for any GitHub README. Pick label, value, colors and one of four styles (flat, flat-square, fo...

JWT Encoder / Signer — Build and sign a JWT — pick HS256 / HS384 / HS512, paste a header and payload (JSON), provide your secret, get a signed token. Us...

MIME Type Lookup — Type a file extension (or filename) and get the proper <code>Content-Type</code> header value. Reverse lookup too — type a MIME type ...

JSON to Go Struct — Paste a JSON sample and get matching Go struct definitions — with optional <code>json:"..."</code> tags, <code>omitempty</code>, and...

JSON to JSON Schema — Paste any JSON sample and get a JSON Schema describing its shape — useful for API documentation, request/response validation, and ...

JSON to Zod Schema — Paste JSON and get a ready-to-use <code>z.object({...})</code> Zod schema plus the inferred TypeScript type.

HTML to Markdown Converter — Paste any HTML snippet — from a blog post, a CMS export, or a webpage — and get clean Markdown ready for static site genera...

Pick any color and get its HEX, RGB, HSL, and HSV values instantly. Free online color picker with eyedropper and color harmony.

.htaccess Generator — Generate .htaccess rules for common Apache web server configurations — redirects, caching, password protection, hotlink blocking, ...

Minify CSS code online. Remove comments, whitespace, and unnecessary characters to reduce file size. Free CSS minifier — instant results.

Minify HTML code online. Remove comments, collapse whitespace, and reduce file size. Free HTML minifier — instant results in your browser.

Parse any URL into its components: protocol, hostname, port, path, query parameters, and hash. Free online URL parser tool.

Parse user agent strings to identify browser, operating system, and device type. Free online user agent parser with instant results.

QR Code Reader — Upload a QR code image to decode its contents. Supports drag-and-drop, file upload, and clipboard paste. Extracts URLs, text, and other...

MIME Type Checker — Enter a file extension or MIME type to look up the corresponding type. Supports 160+ common file formats including web, office, medi...

JavaScript Minifier — Paste your JavaScript code to minify it instantly. Removes comments, collapses whitespace, strips console.log and debugger stateme...

RGB to HEX Converter — Convert between RGB, HEX, HSL, and RGBA color formats with a live color preview. Enter a value in any format and see all conversi...

Generate HTML table markup from delimited text data. Supports tab, comma, CSV, and custom delimiters. Free online HTML table generator.

Barcode Reader — Upload an image containing a barcode or QR code to instantly decode its content. Supports multiple barcode formats.

Free online file MIME type checker. Upload any file to detect its MIME type, file extension, description, and size.

Free side-by-side text comparison tool. Highlight line differences and character-level additions or deletions instantly inside your browser.

Code Diff & Merge — Compare two code snippets side-by-side. View additions and deletions with syntax highlighting, and merge changes interactively with ...

Data Format Converter — Convert between structured data formats instantly. Parse and serialize JSON, YAML, TOML, and XML with configurable indentation a...

JSON Schema Builder — Build JSON validation models visually. Configure properties, toggle required attributes, and instantly copy JSON Schema, Zod code,...

Regex Explainer — Deconstruct regular expressions. Analyze quantifiers, capture groups, sets, boundaries, and flags with clear explanations.

Base64 Inspector — Analyze and validate Base64 content. Inspect MIME headers, calculate overhead size, preview file assets, and download decoded binary ...

SQLite Studio & Viewer — Explore, query, and convert SQLite databases in your browser. Runs entirely client-side using WebAssembly database execution.

Free online code minifier. Compress HTML, CSS, and JavaScript code instantly in one place. Removes comments, whitespace, and formatting to optimize speed.

Generate JSON-LD structured data for Article, Product, LocalBusiness, FAQPage, Organization, BreadcrumbList, and Event schema types instantly.

Paste your URLs and generate a valid XML sitemap with changefreq, priority, and lastmod. Download sitemap.xml instantly — no signup needed.

Visually craft CSS border-radius — independent corners, px/%/em units, and organic blob shapes. Live preview and copy-paste CSS. Runs in your browser.

Design frosted-glass CSS with live preview — blur, saturation, fill opacity, border and shadow. Copy backdrop-filter CSS. Runs in your browser.

Create CSS clip-path shapes visually — polygons, circles, insets and 20+ presets with draggable points. Live preview and copy-paste CSS, in your browser.

Design CSS cubic-bezier easing curves with a draggable editor, presets, and a live animation preview. Copy the timing-function CSS, all in your browser.

Design CSS text-shadow visually — stack multiple layers, pick neon, 3D, outline and retro presets, then copy the CSS. Live preview, runs in your browser.

Build soft-UI neumorphism CSS visually — base color, light direction, shape and shadow distance. Copy box-shadow CSS. Live preview in your browser.

Make CSS triangles with the border trick — choose direction, width, height and color, preview live, and copy the width/height/border CSS. Runs in browser.

Visually build a CSS filter — blur, brightness, contrast, grayscale, hue, sepia and drop-shadow — preview on your own image and copy the CSS. In-browser.

Build CSS transforms visually — translate, scale, rotate, skew plus 3D rotateX/Y/Z and perspective. Live preview on a grid and copy the CSS, in-browser.

Build CSS @keyframes animations — fade, slide, bounce, pulse, spin, flip, zoom — tune duration, easing, delay and loop, preview live and copy the CSS.

A visual CSS flexbox playground — tweak direction, justify, align, wrap and gap, watch the live preview, and copy the container CSS. Runs in your browser.

A visual CSS grid playground — set columns, rows, gaps and track sizing, watch the live preview, and copy the generated grid CSS. Runs in your browser.

Design a CSS button visually — padding, colors, gradients, border-radius, shadow and hover effects — with a live preview, then copy the CSS. In-browser.

Style custom scrollbars visually — width, track and thumb colours, hover and radius — with a live WebKit preview and Firefox fallback. Copy the CSS.

Calculate file or text hashes online — MD5, SHA-1, SHA-256, SHA-512. Verify file integrity by comparing a known checksum. Free, in your browser.

Inspect a PDF's internal structure as formatted JSON. See objects, streams, cross-reference tables, and page trees. Developer tool, in-browser.

Free online monitor test: solid colors, gradients, grid patterns. Find dead pixels, check backlight bleed, test screen uniformity — all in your browser.

Free dead pixel test: full-screen solid colors to find stuck or dead pixels on any monitor, phone, or tablet. No download — runs in your browser.

Screen uniformity test: check for backlight bleed, uneven brightness, and color shifts. Full-screen gray and color patterns for any monitor or display.

Write HTML, CSS, JS in tabbed editors with live iframe preview. Auto-run, download as HTML file. Preloaded counter app sample. No server — pure browser.

Free monitor response time test with flying square UFO ghosting and pursuit camera bar patterns. Measure pixel response and see ghosting on your display.

Monitor viewing angle test with colored wedges and grayscale ramp. Detect color shifts, brightness drop-off, and IPS glow on your display.

Simulate protanopia, deuteranopia, tritanopia, and achromatopsia color blindness on images. Upload a photo or use the built-in test pattern.

Calculate and compare CSS selector specificity instantly. See (a,b,c) breakdown, visualize with bar charts, and find which selector wins. Free developer tool.

Paste SVG path data and see it rendered live. View control points for bezier curves. Supports all path commands (M, C, S, Q, T, A, Z). Free developer tool.

Interactive searchable reference for all HTTP status codes (1xx-5xx). Click to copy, filter by category. Free developer tool, no signup.

Free online Markdown editor with live preview, toolbar, GFM tables, RTL direction support for Arabic, Persian, Urdu, Hebrew. Download as HTML or Markdown. No signup.

Free online css unit converter. No signup, no upload — works entirely in your browser. Fast, private, and free forever.

Free online api tester. No signup, no upload — works entirely in your browser. Fast, private, and free forever.

Free online json toolkit. No signup required.