Free Online Developer Tools — Format, Test & Debug in Your Browser
A full developer toolbox in the browser: regex testing, API requests, SQL and GraphQL formatting, UUID generation, timestamps, JWT decoding, diffs, and schema viewers. No install, no signup, and your code never leaves your machine.
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Regex Tester & Builder
Test and build regular expressions with real-time matching and detailed explanations.
- Regex testing
- Pattern builder
- Match highlighting
UUID Generator
Generate universally unique identifiers with support for different versions and bulk generation.
- Multiple UUID versions
- Bulk generation
- Multiple formats
UUID v4 Generator
Generate random UUID v4 identifiers instantly — single or bulk up to 1000, in standard, compact, braces, or URN format.
- Random 122-bit UUIDs
- Bulk generation up to 1000
- Standard, compact, braces, URN
UUID v7 Generator
Generate time-ordered UUID v7 identifiers — sortable, database-friendly, RFC 9562 compliant. Single or bulk up to 1000.
- RFC 9562 time-ordered UUIDs
- Sortable & index-friendly
- Bulk generation up to 1000
XSD Schema Viewer
Open and explore XML Schema Definition (XSD) files with interactive type navigation and detailed property analysis.
- Interactive type explorer
- Property navigation
- Search & filter
Online Diff Checker
Compare two text documents side-by-side with highlighted differences. Line-by-line comparison with additions, deletions, and modifications.
- Side-by-side comparison
- Line-by-line diff
- Highlighted changes
Unix Timestamp Generator & Converter
Convert between Unix timestamps and human-readable dates. Generate current timestamps, convert to different timezones, and understand epoch time.
- Current timestamp generation
- Unix to date conversion
- Multiple timezone support
SQL Formatter & Beautifier
Format and beautify SQL queries with syntax highlighting, multiple dialect support, and customizable formatting options.
- Multiple SQL dialects
- Syntax highlighting
- Custom formatting options
Regex Offline AI
AI-powered Regex Generator. Generate, test, and validate regular expressions with AI assistance.
- AI-assisted regex generation
- Real-time testing
- Validation and debugging
Code Snippet Screenshot
Create beautiful screenshots of code snippets with customizable backgrounds, syntax highlighting, and social media branding. Perfect for sharing on Twitter, LinkedIn, and presentations.
- Monaco Editor integration
- 20+ programming languages
- 10 beautiful gradients
Crontab Generator
Build and understand cron expressions with live description and next run times. Includes presets and cheatsheet.
- Cron expression builder
- Natural language description
- Next run times
JSON to TypeScript Converter
Convert JSON objects to TypeScript interfaces instantly with customizable options and clean code generation.
- Nested object support
- Array type inference
- Optional/readonly modifiers
GraphQL Schema Viewer
Visualize, validate, and explore GraphQL schemas (SDL) with an interactive type explorer and beautifier.
- GraphQL Interactive type explorer
- GraphQL Schema validation
- GraphQL Syntax highlighting
JWT Decoder / Encoder
Instantly decode, verify, and generate JSON Web Tokens (JWT) locally in your browser. Supports HS256, RS256, and more.
- Decode JWT
- Verify Signature
- Encode & Sign JWT
Open Graph Preview
Preview and debug your Open Graph (OG) meta tags and Twitter Cards instantly. Auto-fetch from URLs.
- Real-time multi-platform previews
- Auto-fetch URL metadata
- X (Twitter), Facebook, LinkedIn & Discord
API Testing Tool
Test your REST APIs online instantly. A fast, free, and 100% client-side browser API testing tool with syntax highlighting, code snippets, and detailed responses.
- Support all HTTP Methods
- Pretty-print JSON Response
- Code snippet generation
Hash Generator
Secure, client-side hash generator supporting MD5, SHA-256, bcrypt, and more. Hash texts or files instantly offline.
- MD5, SHA, and bcrypt algorithms
- Text and local File hashing
- Configurable Cost Factor (Rounds)
MD5 Hash Generator
Generate MD5 checksums from text or files instantly. 100% client-side — verify downloads and deduplicate files without uploading anything.
- Live MD5 hashing of text
- File checksums up to 100MB
- Lowercase / UPPERCASE output
SHA-256 Hash Generator
Compute SHA-256 hashes of text and files instantly. 100% client-side — verify release checksums and fingerprint data without uploading anything.
- Live SHA-256 hashing of text
- File checksums up to 100MB
- Lowercase / UPPERCASE output
JSON Semantic Diff & Compare
Compare two JSON objects semantically using our privacy-first, client-side tool. Identify structural differences, ignore key order and formatting effortlessly.
- Semantic Object Comparison
- Sort JSON Keys
- Format JSON
OpenAPI & Swagger Viewer
Open an OpenAPI 3.x or Swagger 2.0 file in JSON or YAML and explore endpoints, parameters, schemas, and responses in an interactive UI.
- OpenAPI 3.x & Swagger 2.0
- JSON & YAML support
- Live Try It Out
LLM Token Counter
Count tokens and estimate API cost for GPT-5, GPT-4o, Claude, Gemini, Llama and more — exact tiktoken counts, 100% in your browser.
- Exact tiktoken token counts
- Cost & pricing calculator
- 18+ models compared side by side
GraphQL Formatter & Beautifier
Format, validate, and beautify GraphQL queries, mutations, and schemas with syntax highlighting and query analysis.
- GraphQL formatting & beautifying
- Real-time syntax validation
- Query analysis & minification
GraphQL Minifier
Minify GraphQL queries and schemas into compact single-line strings — smaller payloads, ready to embed in code.
- One-click GraphQL minification
- Whitespace-safe compaction
- Re-format back to readable
GraphQL Validator
Validate GraphQL queries, mutations, and schemas as you type — syntax errors flagged with line numbers, plus query analysis.
- Real-time syntax validation
- Errors with line numbers
- Operation & field analysis
Password Generator
Generate strong random passwords with cryptographically secure randomness — length, character sets, and strength meter, all on your device.
- Web Crypto secure randomness
- Length & character set controls
- Entropy-based strength meter
About Developer Tools
Digital ToolPad's developer tools are 26 free, privacy-first utilities that run entirely in your browser. This collection includes Regex Tester & Builder, UUID Generator, UUID v4 Generator, UUID v7 Generator, XSD Schema Viewer, Online Diff Checker, Unix Timestamp Generator & Converter, SQL Formatter & Beautifier, Regex Offline AI, Code Snippet Screenshot, Crontab Generator, JSON to TypeScript Converter, GraphQL Schema Viewer, JWT Decoder / Encoder, Open Graph Preview, API Testing Tool, Hash Generator, MD5 Hash Generator, SHA-256 Hash Generator, JSON Semantic Diff & Compare, OpenAPI & Swagger Viewer, LLM Token Counter, GraphQL Formatter & Beautifier, GraphQL Minifier, GraphQL Validator and Password Generator. There's no signup and nothing to install — open any tool and start in seconds, on Windows, macOS, Linux, or your phone.
Every tool processes your data locally using modern web technology, so your files and text never leave your device — zero uploads, zero tracking. You can confirm it yourself by opening your browser's Network tab while you work, which makes these developer tools a safe choice for sensitive or confidential content.
Private by design
Your files and text are processed on your device — nothing is uploaded. Verify it in your browser's Network tab.
Free, no signup
Every tool works instantly — no account, no trial limits, no credit card.
Works everywhere
Windows, macOS, Linux, or your phone — anywhere a modern browser runs.
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JSON Tools
7 toolsOur free JSON tools run 100% locally in your browser, keeping your data private. Whether you need to format, validate, or convert JSON, these tools are fast, secure, and built for developers.
View collectionEncoding Tools
8 toolsEncode and decode Base64, URLs, and JWTs, and generate MD5 or SHA-256 hashes — entirely in your browser. Built for developers who don't want to paste tokens and secrets into someone else's server.
View collectionText Tools
11 toolsCount words and characters, convert text case, compare documents, remove duplicate lines, and write distraction-free — all in your browser. No signup, and your text never leaves your device.
View collectionAI Tools
4 toolsOur free AI tools run entirely in your browser using WebGPU and WebAssembly — chat with an offline LLM, generate regex from plain English, count LLM tokens, and more. No API keys, no signup, and your prompts never leave your device.
View collectionFrequently asked questions
Why use these instead of installing a desktop toolbox app?
You get the same utilities with nothing to install, on any OS — Windows, Mac, Linux, or even a locked-down work machine — and unlike paid desktop toolboxes, everything here is free.
Can I use these tools with proprietary code and data?
Yes. Every tool processes input locally in your browser, so proprietary code, API payloads, and connection strings never leave your machine. Verify it yourself in the browser's Network tab.
Do these tools work offline?
Most do — once the page is loaded, formatting, generating, and testing run entirely client-side without any server round-trips.
Explore more free, private tools
Bookmark this page and browse the full Digital ToolPad library — 82+ privacy-first tools for developers, creators, and everyday tasks, all running 100% in your browser.
Explore other tool collections
More free, privacy-first tools grouped by what you need to get done.
JSON Tools
Our free JSON tools run 100% locally in your browser, keeping your data private. Whether you need to format, validate, or convert JSON, these tools are fast, secure, and built for developers.
YAML Tools
Our free YAML tools run 100% locally in your browser, keeping your data private. Whether you need to format, validate, or convert YAML, these tools are fast, secure, and built for developers.
Markdown Tools
Our free Markdown tools help you write, convert, and preview Markdown documents with ease. Whether you're a developer or a writer, these tools are designed to enhance your productivity.
PDF Tools
Our free PDF tools allow you to convert, view, and manage PDF documents easily. Whether you need to convert PDFs to other formats or vice versa, these tools are user-friendly and efficient.
AI Tools
Our free AI tools run entirely in your browser using WebGPU and WebAssembly — chat with an offline LLM, generate regex from plain English, count LLM tokens, and more. No API keys, no signup, and your prompts never leave your device.
Base64 Tools
Our free Base64 tools allow you to convert, view, and manage Base64 strings easily. Whether you need to convert Base64 strings to images or vice versa, these tools are user-friendly and efficient.
Image Tools
Convert, resize, compress, and clean up images without uploading them anywhere. WebP, HEIC, PNG, and JPG conversion, background removal, metadata stripping, favicons, and more — every tool runs 100% on your device.
Text Tools
Count words and characters, convert text case, compare documents, remove duplicate lines, and write distraction-free — all in your browser. No signup, and your text never leaves your device.
Encoding Tools
Encode and decode Base64, URLs, and JWTs, and generate MD5 or SHA-256 hashes — entirely in your browser. Built for developers who don't want to paste tokens and secrets into someone else's server.
Productivity Tools
Simple, free tools for everyday work and life: a Pomodoro timer, world time zone converter, online notepad, random name picker, password generator, and more. No accounts, no installs — open a tab and go.
Health Tools
Free health and fitness calculators that run entirely in your browser: check your BMI and weight category, estimate your maintenance calories, and plan from there. No signup — and your health data never leaves your device.