Free Online Developer Tools and AI Utilities

TechFolks gives developers, QA engineers, students, and AI-assisted coding workflows a fast set of browser-friendly tools for formatting JSON, practicing SQL, testing APIs, decoding JWTs, parsing cron schedules, converting timestamps, checking network data, and preparing image or PDF files.

Built for quick work: free access, copy-friendly output, practical samples, mobile-friendly pages, and browser-side processing where supported.

Popular Tools

JSON Formatter and Validator

Paste JSON, validate structure, beautify or minify it, and inspect nested values in a readable tree view.

Best for API payloads, logs, configuration files, and AI-generated JSON.

SQL Practice and Formatter

Run SQL lessons, format queries, and convert common syntax patterns between DB2, Oracle, MySQL, and SQL Server.

Best for interviews, DBMS learning, and migration cleanup.

Online REST API Client

Send public HTTP requests with headers, body, auth helpers, response metadata, local history, and cURL output.

Best for testing sample APIs without opening a full desktop client.

AI Developer Toolkit

Use one page for JSON/YAML conversion, password generation, hashing, HTTP status lookup, minifying, Markdown preview, and mock API output.

Best for everyday development chores.

Decoder Tools

Decode Base64, inspect JWT payloads, and test regular expressions with quick examples.

Best for API debugging and token inspection.

Image to PDF Converter

Convert screenshots, JPG, PNG, and BMP images into a clean PDF with optional captions and a document title.

Best for QA reports, issue evidence, and simple documentation.

More Utilities

What To Learn Next

New visitors usually arrive with one specific problem. Start with a tool, then use the related guides and examples to solve the next step: validate JSON before testing an API, format SQL before practicing joins, or compress screenshots before creating a PDF report.

Read TechFolks blogs or scan technology news after you finish the task.