Free Utilities - Developer Tools

SQL Generator

Describe what you want in plain English, get SQL. Supports PostgreSQL, MySQL, SQL Server, and SQLite.

Generate SQL →

JWT Decoder

Decode and inspect JSON Web Tokens. View header, payload, and signature details with syntax highlighting.

Decode a token →

JSON Formatter

Beautify, minify, and validate JSON data. Perfect for debugging API responses or formatting configuration files.

Format JSON →

Code Explainer

Paste code, get a plain English explanation. Supports all major programming languages.

Explain code →

Diff Checker

Compare two text blocks and see the differences highlighted. Perfect for code reviews and config changes.

Compare text →

Base64 Encoder/Decoder

Encode text to Base64 or decode Base64 strings. Supports URL-safe encoding and Unicode.

Convert Base64 →

Markdown Previewer

Write and preview Markdown in real-time. Supports GitHub Flavored Markdown with syntax highlighting.

Preview Markdown →

Email Tone Adjuster

Adjust your email's tone to be more professional, casual, friendly, or assertive. AI-powered rewriting.

Adjust tone →

Code to Diagram

Generate class diagrams, sequence diagrams, ER diagrams, and flowcharts from code or descriptions. AI-powered Mermaid generation.

Generate diagram →

Security Header Checker

Check HTTP security headers of any URL and get a security grade (A-F) with detailed findings and recommendations.

Check headers →

API Tester

Test REST APIs directly in your browser. Send requests, inspect responses, and generate code snippets.

Test an API →

OAuth Flow Visualizer

Interactive step-by-step visualization of OAuth 2.0 and OpenID Connect authentication flows.

Explore flows →

Clustered vs Non-Clustered Index

Interactive clustered vs non-clustered index comparison. Visualize B-tree seeks, key lookups, and covering indexes.

Explore indexes →

B-Tree Visualizer

Explore SQL Server B-tree index structure. See how key size affects tree depth and simulate index seeks with animated I/O cost.

Explore B-trees →

Execution Plan Visualizer

See how indexes change query performance. Interactive visualization of scans vs seeks, key lookups, and covering indexes.

Visualize plans →

Index Overhead Visualizer

See why too many indexes hurt writes. Visualize write amplification, storage cost, and maintenance tradeoffs interactively.

Explore overhead →

SOAP REST Gateway

Generate a modern REST API with Swagger in front of any SOAP/WSDL service. Download and add to your solution.

Generate gateway →

Invoice Generator

Create professional PDF invoices in seconds. Add line items, calculate totals, and download a polished invoice.

Create invoice →