Tech : 443

All Developer Tools

11 free utilities for developers, testers, and security engineers. Every one runs entirely inside your browser — no account, no upload, no server ever sees your data.

Password & Hash Tools

Hash Generator

Generate SHA-1, SHA-256, and SHA-512 hashes from any text for checksums, data integrity verification, and security testing.

Random Password Generator

Create strong, customizable passwords with configurable length and character sets for enhanced account security.

Data Conversion Tools

CSV to JSON Converter

Transform CSV data into JSON format instantly. Perfect for API development, data migration, and web applications.

Base64 Encoder/Decoder

Encode text to Base64 or decode Base64 strings. Essential for data transmission and binary-to-text conversion.

URL Encoder / Decoder

Percent-encode and decode URLs and query strings. Switch between component and full-URL encoding, handle + as space, and inspect any URL parameter by parameter.

Formatting & Utility Tools

JSON Formatter & Validator

Beautify, validate, and format JSON data with syntax highlighting. Ideal for debugging and data visualization.

JSON Diff Checker

Compare two JSON documents side by side. Instantly highlight added, removed, and changed values — perfect for API debugging and config review.

File & Text Diff Checker

Compare two text files or blocks of text line by line. Highlight added, removed, and changed lines — ideal for config review, log analysis, and code review.

Timestamp to Date Converter

Convert Unix timestamps to human-readable dates and vice versa. Essential for log analysis and time-based data.

Security & Testing

JWT Decoder & Verifier

Decode JSON Web Tokens to inspect header, payload, and claims. Human-readable expiry, security warnings, and in-browser HS256 signature verification.

API Security Testing Tool

Probe API endpoints for common security misconfigurations and response issues, right from your browser.

Why These Tools Run in Your Browser

Most online developer utilities are thin front-ends over a server API: you paste a token, a config file, or a database dump into a text box, and it gets POSTed to somebody else's machine before you see a result. That is fine for a sample payload and a serious problem for anything real. Access tokens, customer exports, internal API responses, and staging credentials are all things people paste into tools like these every day.

Every utility on this page is built the other way round. The page is a static file, the logic is plain JavaScript, and the work happens on your own device using browser primitives — TextEncoder, the Web Crypto API, btoa/atob, JSON.parse, Intl.DateTimeFormat. There is no backend to send data to. You can confirm it: open your browser's network panel, use any tool, and watch that no request leaves the page.

What That Means in Practice

  • No upload, no retention. Nothing you type is transmitted, so there is nothing to log, cache, breach, or subpoena.
  • Works offline. Once a tool page has loaded, it keeps working with the network disconnected — useful on locked-down corporate machines and in air-gapped environments.
  • No sign-up and no rate limits. There is no account system because there is no server-side state to attach an account to.
  • Fast. Results appear as you type, because there is no network round trip between input and output.

Choosing the Right Tool