Developer Tools
Developer tools cover the everyday tasks that software engineers perform dozens of times a day: formatting and validating data, encoding and decoding strings, testing patterns, inspecting tokens, and generating identifiers. This collection brings those utilities together in one place, each running entirely in your browser so you can paste sensitive data — API responses, tokens, config files — without it ever touching a server. Whether you are debugging an API payload, verifying a downloaded file, or generating a UUID for a new database row, these tools remove the friction of context-switching between desktop apps and sketchy online services.
Developer Tools (11)
JSON Formatter
Format, validate, and beautify JSON data instantly. Parse and fix malformed JSON with syntax highlighting.
Base64 Encoder / Decoder
Encode text to Base64 or decode Base64 strings back to plain text. Supports UTF-8 and binary data.
URL Encoder / Decoder
Encode special characters for URLs or decode percent-encoded URLs back to readable text.
Timestamp Converter
Convert Unix timestamps to human-readable dates and vice versa. Supports seconds and milliseconds.
Markdown Previewer
Write and preview Markdown in real-time. See how your Markdown renders as HTML instantly.
Regex Tester
Test regular expressions against text with real-time matching. See matches, groups, and replacements.
UUID Generator
Generate random UUIDs (v4) and GUIDs. Copy with one click. Perfect for developer testing.
Hash Generator
Generate MD5, SHA-1, SHA-256, SHA-384, and SHA-512 hashes from any text input.
JWT Decoder
Decode JWT tokens and inspect the header, payload, and signature. No data is sent to any server.
HTML Entity Encoder / Decoder
Encode special HTML characters to entities and decode HTML entities back to readable text.
Text Diff Checker
Compare two texts and find differences instantly. See what was added, removed, or changed line by line.
Developer Tools — Frequently Asked Questions
Can I use these developer tools with sensitive data?
Yes. Every tool runs entirely in your browser using client-side JavaScript, so nothing you paste — API keys, tokens, config files — is ever uploaded to a server. This makes them safe for use with real production data during debugging.
Do the tools support large inputs?
Most tools handle inputs of several megabytes comfortably. The practical limit is browser memory and rendering speed rather than the algorithms themselves. For extremely large files, split them into smaller chunks for the best experience.
Are these tools open source?
The tools are free to use for any purpose. The processing logic relies on well-established open-source libraries such as marked, crypto-js, and qrcode, running locally in your browser.
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