The Developer's
Toolbox Reimagined
Format, diff, convert, debug, and secure your code — all without installing anything or trusting a server. Zero uploads. Infinite privacy.
Runs Locally
All tools run entirely in your browser. Your data never leaves your machine — not even for a millisecond.
Blazing Fast
Optimized with zero backend dependency. Handle massive payloads without freezing or waiting for servers.
Developer First
Monaco editors, keyboard shortcuts, dark mode, command palette — built by developers, for developers.
Always Free
Every tool is completely free to use. No login required, no usage limits. Open your browser and start building.
Trending Tools
JSON Diff & Merge
Monaco EditorLive VS Code-style comparison with recursive key sorting, A/B swapping, and inline merge.
JSON Formatter
Most UsedFormat, validate, and minify massive JSON files instantly in your browser.
JWT Decoder
PopularDecode and inspect JSON Web Tokens locally — see header, payload, and expiry at a glance.
AI WorkbenchNew
Tools for the AI era — where interactive exploration beats generic chat prompts
LLM Token Counter
NewCount tokens for GPT-4o, GPT-4, and Claude. Includes cost estimation and character counts.
AI Prompt Comparator
Prompt Eng.Side-by-side prompt diff with variable injection and word-level visual highlighting.
Smart Data Extractor
Local FirstExtract emails, URLs, phone numbers and custom regex from any text — 100% local.
Visual State Machine
Logic ToolsDesign states + transitions visually, then export XState JSON or a TypeScript reducer.
Security & PerformanceNew
Audit your headers, trace bottlenecks, and harden your stack
CSP & Headers Builder
SecurityBuild Content-Security-Policy interactively. Live A+–F security grade + Nginx/Apache export.
Perf Trace Explorer
PerformanceUpload a Chrome trace file and visualize a Gantt timeline. Spot Long Tasks instantly.
Security Headers
Inspect and grade your HTTP security headers like HSTS, X-Frame-Options, and CSP.
Bcrypt Generator
Hash and verify passwords with bcrypt — the gold standard for password security.
JSON & Data
Every JSON operation you'll ever need — parse, diff, query, convert
JSON Diff & Merge
MonacoLive VS Code-style comparison with recursive key sorting and A/B swapping.
JSON Formatter
Format, validate, and minify massive JSON files instantly.
JSON Schema Generator
Auto-generate a JSON Schema from any JSON sample.
JSONPath Tester
Query JSON with JSONPath expressions and see results live.
JSON to TypeScript
Convert a JSON object into TypeScript interfaces instantly.
JSON to Zod Schema
Generate Zod validation schemas from JSON samples.
Mock Data Generator
NewGenerate up to 10,000 rows of realistic fake data. 25+ field types, JSON/CSV export.
JSON Schema Validator
NewValidate JSON against Draft-07 schemas — per-field errors with JSONPath pointers. No uploads.
Converters
Transform data between any format with zero friction
CSV ↔ JSON
Bidirectional conversion between CSV tables and JSON.
YAML ↔ JSON
Convert YAML configurations to JSON and back.
XML ↔ JSON
Parse and convert XML to JSON, or the reverse.
Base64 Encode/Decode
Encode and decode Unicode strings with full emoji support.
URL Encode/Decode
Encode query parameters and decode URL-encoded strings.
HTML to JSX
Convert HTML markup to React JSX with one click.
Number Base Converter
NewBinary ↔ Octal ↔ Decimal ↔ Hex with 8/16/32/64-bit visualization.
Auth & Crypto
JWT, RSA, hashes, passwords — all computed locally without ever touching a server
DevOps & Infrastructure
Cron expressions, subnet calculators, and SQL formatting for backend engineers
Cron Generator
Parse and explain cron schedule expressions visually.
CIDR Calculator
Calculate IP ranges, broadcast addresses, and subnets.
SQL Formatter
Format and beautify SQL queries for any dialect.
Unix Timestamp
Convert between Unix timestamps and human-readable dates.
Semantic Versioning
Parse, increment, and compare SemVer 2.0.0 strings.
Cache-Control Builder
Visually build and explain complex HTTP caching headers.
Log Format Parser
Instantly analyze and filter JSON, Nginx, and Apache logs.
npm Bundle Size Checker
Estimate minified and gzipped sizes of npm packages.
Productivity & Text
Case converters, diff, regex, markdown — the everyday text utilities
Case Converter
Transform text between camelCase, snake_case, PascalCase and more.
Text Diff Checker
Compare two texts line-by-line to find additions and deletions.
Markdown Previewer
Live split-view Markdown editor and renderer.
URL Parser & Builder
Deconstruct and manage complex query strings visually.
Regex Debugger
VisualVisual match highlighting and capture-group tracking in real-time.
Design & CSS
Color pickers, gradient builders, glassmorphism, SVG tools — for frontend crafters
Color Tool
Convert, pick, and explore color values across formats.
Color Contrast Checker
A11yWCAG 2.1 AA/AAA contrast ratio calculator with live preview. Build accessible UIs.
CSS Gradient Builder
Build beautiful linear and radial CSS gradients visually.
Glassmorphism
Design frosted-glass UI cards and generate the CSS.
SVG Pattern
Generate tileable SVG background patterns with live preview.
Flexbox Playground
Experiment with Flexbox layout properties visually.
SVG Optimizer
Strip bloat from SVG files and minify them for production.
Clip-Path Builder
Visually create complex CSS clip-path shapes with presets.
Typography Scale
Generate harmonious typographic hierarchies with modular scales.
CSS Grid Builder
Design complex grid layouts visually with areas and tracks.
Easing Visualizer
Design custom cubic-bezier easing functions for smooth animations.
What is DToolkits?
DToolkits is a professional, privacy-first developer toolsuite designed for modern software engineers. All tools run entirely in your browser — your data is never uploaded to any external server. Whether you are formatting JSON, debugging a regex, inspecting a JWT, or calculating CIDR subnets, DToolkits provides instant, reliable results with zero configuration.
Unlike generic AI chat interfaces, DToolkits delivers deterministic, visual, and interactive tooling — exact outputs every time, with visual feedback like Gantt timelines, state machine simulators, and live security grading that no chatbot can replicate.
Comprehensive Encode, Decode, and Security Suite
Beyond JSON formatting, DToolkits offers a robust suite of text and security utilities. Need to handle query parameters? Our URL Encoder / Decoder safely converts special characters. Dealing with web tokens? Use our Base64 Encoder / Decoder to safely translate binary data into ASCII strings. For security architects, our CSP & Headers Builder generates Content-Security-Policy headers with live A+–F grading, and our Bcrypt Generator hashes passwords with the industry-standard algorithm.