Developer Tools

Developer Tools — Utilities for Web Developers and Programmers

Developers constantly need small utility operations — hash a string, encode something to Base64, format a JSON blob, check a regex, generate a UUID, convert a colour — that don't justify opening a terminal or writing a script. This collection brings the most common developer micro-tasks together in one place so you can do them without breaking your workflow.

What's included

Hash generator (MD5, SHA-1, SHA-256, SHA-512): Hash any text string and compare the result against a known hash for verification. Useful for checking data integrity, testing hash-based signatures, or understanding how password hashing works.

Base64 encoder/decoder: Convert text or image data to and from Base64. Used in API development, embedding images in CSS/HTML, decoding JWT token payloads, and HTTP Basic Auth headers.

URL encoder/decoder: Percent-encode characters for safe use in URLs, or decode an encoded URL to read it. Handles both encodeURIComponent and encodeURI conventions.

JSON formatter and validator: Format minified JSON to readable indented form and validate syntax. Reports the exact location of syntax errors.

Regex tester: Test JavaScript regular expressions against sample text with live match highlighting. Supports global, case-insensitive, multiline, and dotall flags. Includes a replace mode for testing substitutions with capture group backreferences.

UUID generator: Generate version 4 UUIDs (randomly generated) in bulk. Download as a text file or copy individually.

Color converter: Convert between HEX, RGB, RGBA, HSL, HSLA, and CMYK. See a live color preview alongside the converted values.

String encoder: Encode and decode across Base64, HTML entities, URL encoding, Unicode escapes, hex, and ROT13.

Common use cases

API development and debugging: Decode Base64 response fields, format JSON API responses, encode query parameters, and test regex for input validation — all without leaving the browser.

Frontend development: Convert design colours from HEX to HSL for CSS variables, generate UUIDs for React list keys or mock data, and format JSON config files.

Security and backend work: Hash strings to verify checksums, check what a Base64-encoded credential decodes to, or test a validation regex for email, phone number, or PAN card format before adding it to the codebase.

Debugging encoded data: JWTs are Base64-encoded JSON. When debugging authentication issues, decode the payload section of a JWT here to inspect the claims without needing a JWT-specific tool. (Note: this is the payload only — never paste a live production token into any web tool.)

Data preparation: When building test fixtures or mock data, generate a batch of UUIDs, format JSON, and encode values as needed — all from one page.

Indian developer context: Validating PAN card format (regex: /^[A-Z]{5}[0-9]{4}[A-Z]{1}$/), Aadhaar number format (12 digits), GST number format (15-character alphanumeric with state code) — test these patterns in the regex tester before adding them to your validation code.

Tips

For debugging, use these tools on sample or sanitised data — never paste production credentials, API keys, database passwords, or personal user data into any online tool, including this one. All processing here is client-side (your browser only), but safe habits matter regardless.

The regex tester uses JavaScript's regex engine. If you're targeting Python, Java, Go, or another language, test in a language-specific environment before relying on the match behaviour — regex dialects differ in lookbehind support, named groups, and some escape sequences.

Limitations

These are utility tools for common developer tasks, not a full IDE or debugging environment. There's no code execution, no network request inspection, and no file system access. For comprehensive development tooling, your code editor (VS Code, JetBrains) and browser DevTools are the right place — these utilities supplement them for quick operations rather than replacing them.

Processing is done in the browser, which means very large inputs (multi-megabyte JSON files, enormous text blocks) may be slow or hit browser memory limits. For large-scale data processing, command-line tools (jq for JSON, openssl for hashing) are more efficient.