The developer workbench
Find your next shortcut.
Small, focused tools for the work between the big ideas. Pick a task, make it yours, and get back to building.
50 tools available
Browser-based · No accountNo matching tools.
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CSS Tools
- CSS / Tool
Flexbox Generator
Configure direction, alignment, wrapping, and spacing for a CSS flex container.
- CSS / Tool
Box Shadow Generator
Adjust a CSS shadow’s offset, blur, spread, color, and opacity with a live preview.
- CSS / Tool
Button Generator
Style a button’s label, spacing, border, and colors, then copy its HTML and CSS.
- CSS / Tool
Gradient Generator
Create linear or radial CSS gradients with three adjustable color stops.
- CSS / Tool
CSS Formatter
Format CSS with Prettier and consistent indentation, spacing, and line breaks.
- CSS / Tool
Color Converter
Convert HEX, RGB, and HSL colors with alpha support and a color preview.
- CSS / Tool
Contrast Checker
Calculate text contrast and compare it with WCAG AA and AAA thresholds.
- CSS / Tool
CSS Grid Generator
Build fixed or responsive CSS grids with adjustable tracks and gaps.
- CSS / Tool
Fluid Typography Clamp Generator
Generate a CSS clamp value between chosen font sizes and viewport widths.
- CSS / Tool
PX to REM Converter
Convert pixels and rem units using your chosen root font size.
- CSS / Tool
Border Radius Generator
Adjust four independent corner radii and copy the matching CSS.
- CSS / Tool
CSS Selector & Specificity Lab
Calculate selector weights, resolve CSS nesting, and inspect matches against inert sample HTML.
- CSS / Tool
CSS Animation & Easing Builder
Build transform and opacity keyframes, tune cubic Bézier easing, and export CSS with a reduced-motion fallback.
- CSS / Tool
Palette & Design Tokens
Build named color ramps, assign interface roles, check text contrast, and export CSS variables or JSON tokens.
- CSS / Tool
CSS Clip-path Builder
Create circle, ellipse, inset and polygon clips with numeric geometry and exact CSS export.
- CSS / Tool
CSS Transform & Perspective Playground
Explore transform order, 3D origin and parent perspective with matching CSS and HTML.
- CSS / Tool
CSS Filter & Backdrop Composer
Compose ordered element or backdrop filters with a local before-and-after preview and CSS fallback.
- CSS / Tool
Modular Type Scale & Rhythm Calculator
Calculate modular rem sizes, line heights and spacing rhythm with CSS tokens and CSV export.
HTML Tools
- HTML / Tool
HTML Formatter
Format HTML with Prettier, including embedded CSS and JavaScript.
- HTML / Tool
HTML Table Generator
Turn quoted CSV or TSV into an escaped HTML table with semantic headers.
- HTML / Tool
HTML Entity Encoder & Decoder
Escape HTML text or decode named and numeric character references.
- HTML / Tool
Markdown to HTML
Convert Markdown into sanitized HTML and inspect a sandboxed preview.
- HTML / Tool
HTML & SVG to JSX Converter
Convert HTML and SVG into JSX with React attribute names, style objects, and clear conversion notices.
- HTML / Tool
Responsive Image Markup Builder
Generate escaped img and picture markup with srcset, sizes, dimensions, alt text and loading hints from your existing assets.
- HTML / Tool
SVG Optimizer
Optimize SVG locally with preserved viewBox, IDs and accessible labels, exact output, and a restricted preview.
- HTML / Tool
Responsive HTML & CSS Playground
Edit HTML and CSS, inspect explicit viewport sizes in an isolated preview, and export the exact filtered standalone document.
- HTML / Tool
Accessible Form Builder
Build native fields with labels, help text, required choices, and fieldsets. Check local validity and export a complete form example.
- HTML / Tool
HTML Accessibility Preflight
Check pasted HTML for scoped source issues in labels, ID references, image alternatives, headings, and document metadata. Local parsing with source locations.
JavaScript Tools
- JS / Tool
JavaScript Formatter
Format JavaScript with Prettier without executing your code.
- JS / Tool
JSON Formatter & Validator
Format and validate JSON while preserving numeric precision and detecting duplicate keys.
- JS / Tool
JavaScript Regex Tester
Test JavaScript patterns with match details in a worker that can be stopped.
SEO Tools
- SEO / Tool
Meta Tag Generator
Generate escaped page metadata with an approximate search result preview.
- SEO / Tool
Open Graph & Twitter Card Generator
Create social sharing metadata and inspect an approximate card preview.
- SEO / Tool
Robots.txt Generator
Build robots.txt groups, path rules, and sitemap directives with validation.
- SEO / Tool
JSON-LD Structured Data Builder
Create escaped Article, BreadcrumbList and Organization JSON-LD scripts from your own facts, with local URL and date checks.
- SEO / Tool
Sitemap XML Builder & Validator
Build URL-set or index XML from a URL list or CSV, and check local sitemap structure, namespaces, dates, duplicates and URL scope.
Text Tools
- Text / Tool
Code Diff
Compare code with word or character highlights, then merge selected changes locally.
- Text / Tool
URL Encoder & Decoder
Encode or decode URL components, full URLs, and form values with explicit modes.
- Text / Tool
Unicode Base64 Encoder & Decoder
Encode UTF-8 text as Base64 or decode valid Base64 back into Unicode text.
Data Tools
- Data / Tool
JSON, CSV & YAML Converter
Convert JSON, CSV, and YAML with exact numeric tokens, explicit CSV typing, and spreadsheet export controls.
- Data / Tool
JSON to TypeScript
Infer a TypeScript type from a JSON sample with quoted property keys, nested shapes, mixed array unions, and explicit empty-value limits. Runs locally.
- Data / Tool
JSON Schema Validator
Validate a JSON instance against a bounded Draft 7 schema with Ajv in a cancellable local worker. Read JSON Pointer diagnostics without remote reference requests.
- Data / Tool
Mock Data Generator
Create reproducible fictional records from a seed, choose field types and bounds, and export JSON or escaped CSV.
- Data / Tool
JSONPath Tester
Query local JSON with a bounded RFC 9535 engine and inspect matching values with normalized paths.
- Data / Tool
JWT Inspector
Decode JWT header and payload JSON locally with exact numeric tokens and clear untrusted-claim notices. No signature verification.
- Data / Tool
Unix Timestamp Converter
Convert Unix seconds, milliseconds, and ISO dates with explicit offsets, exact millisecond values, and UTC or IANA timezone displays.
- Data / Tool
UUID Generator & Inspector
Generate secure UUIDv4 and UUIDv7 batches locally, inspect version and variant fields, and extract untrusted v7 timestamps.
- Data / Tool
File Hash & SRI Generator
Hash local file bytes with SHA-256, SHA-384, or SHA-512 and export matching hex, Base64, or SRI values without uploading.