Why these guides exist

The tools on Dev Atlas are intentionally small, but the debugging context around them matters. These guides explain when to use each tool, what common errors mean, and what not to assume from formatted, decoded, converted, or generated output.

9 min read

API Debugging Checklist for Frontend and Backend Developers

A practical step-by-step checklist for debugging API responses, request payloads, auth tokens, timestamps, encoding issues, and reproducible examples.

Open JSON Formatter
8 min read

Best Free Developer Tools for Everyday Debugging

A practical guide to common browser-side developer tools for formatting, decoding, converting, testing, and generating debugging values.

Browse All Tools
6 min read

How to Format and Validate JSON Safely

Learn how to format, validate, minify, and inspect JSON without confusing JavaScript object syntax with valid JSON.

Open JSON Formatter
7 min read

How to Decode a JWT Without Trusting It

Understand JWT header and payload fields, time claims, and why decoding a token is not the same as verifying it.

Open JWT Decoder
6 min read

Unix Timestamp Seconds vs Milliseconds

Learn how Unix seconds, Unix milliseconds, ISO strings, UTC, and local time relate during API and log debugging.

Open Timestamp Converter
5 min read

Base64 Encoding Is Not Encryption

Learn what Base64 is for, how it differs from encryption, and how to decode small payloads safely.

Open Base64 Encoder
6 min read

URL Encoding for Query Strings and Paths

Learn when to encode URL components, why full URLs are different from query values, and how to avoid decode errors.

Open URL Encoder
7 min read

How to Test Regular Expressions Online

Learn how to test JavaScript regular expressions, inspect matches, understand flags, and avoid common pattern mistakes.

Open Regex Tester
7 min read

MD5 vs SHA-1 vs SHA-256: Which Hash Should You Use?

Understand common hash algorithms, safe use cases, and why hashes are not the same as encryption.

Open Hash Generator
7 min read

Cron Expression Guide with Examples

Learn five-field cron syntax, common schedules, and how to preview upcoming run times before shipping jobs.

Open Cron Parser
6 min read

HEX, RGB, and HSL Color Formats Explained

Learn when to use HEX, RGB, and HSL in CSS, how alpha values work, and how to compare color formats safely.

Open Color Converter
6 min read

What Is a UUID and When Should You Use One?

Understand UUID v4 identifiers, common development use cases, and when a UUID is not a replacement for security or database design.

Open UUID Generator