Free Developer Tools

Browser-based utilities for everyday development. No signup, no tracking, no data leaves your machine.

Formatters & Parsers

JSON Formatter & Validator

Format, validate, and beautify JSON data instantly. Catch syntax errors with line numbers.

Stack Trace Parser

Paste a raw stack trace and get it parsed into structured frames with file, line, and function info.

Regex Tester

Test regular expressions with live match highlighting, capture groups, and flag controls.

Encoders & Decoders

Base64 Encode / Decode

Encode text to Base64 or decode Base64 strings back to plain text. Supports UTF-8.

Epoch / Unix Timestamp Converter

Convert between Unix timestamps and human-readable dates. Supports seconds and milliseconds.

JWT Decoder

Decode and inspect JSON Web Tokens. View header, payload, and expiration status.

Generators

UUID Generator

Generate random v4 UUIDs instantly. Bulk generation up to 100 at a time with one-click copy.

Cron Expression Generator

Build cron expressions visually and preview the next scheduled run times.

Reference Guides

HTTP Status Code Reference

Searchable reference of all HTTP status codes with descriptions, common causes, and debugging tips.

Log Levels Reference

Interactive reference mapping log levels across Python, Java, Node.js, Go, and syslog.

Frequently Asked Questions

Are these tools really free?

Yes — every tool is 100% free with no signup, no limits, and no ads. They run entirely in your browser.

Is my data safe?

All processing happens client-side in your browser. No data is sent to any server.

Who built these tools?

These tools are built by Bugsly, an open-source error tracking platform. We built them because we use them every day.