DIGITAL UTILITY KIT
Free Online Developer Tools
A compact toolbox for common development and debugging tasks. Many operations are performed entirely in the browser, making the tools useful for quick checks without a local setup.
Available tools
11 free tools in this category.
JSON Formatter & Validator
Format, minify and validate JSON instantly in your browser.
Open tool →developerURL Encoder & Decoder
Encode and decode URL components instantly in your browser.
Open tool →developerBase64 Encoder & Decoder
Encode Unicode text to Base64 or decode Base64 instantly.
Open tool →developerUUID Generator
Generate secure random UUID v4 identifiers instantly.
Open tool →developerUnix Timestamp Converter
Convert Unix timestamps to dates and dates back to epoch time.
Open tool →developerSHA Hash Generator
Generate SHA-256, SHA-384 and SHA-512 hashes locally.
Open tool →developerJWT Decoder
Decode JWT header and payload instantly without uploading the token.
Open tool →developerRegex Tester
Test JavaScript regular expressions against text instantly.
Open tool →developerColor Converter
Convert colours between HEX, RGB and HSL instantly.
Open tool →developerJSON to CSV
Convert JSON object arrays to CSV instantly.
Open tool →developerCSV to JSON
Convert CSV data to structured JSON instantly.
Open tool →Guides and explanations
Useful background for getting better results from these tools.
JSON vs CSV: Differences, Use Cases and Conversion Tips
One holds shape, the other holds a table. Knowing which problem you have decides the format, and decides what breaks when you convert between them.
Read guide →How to Format and Validate JSON Quickly
Reading an unreadable API response, finding the character that actually broke it, and knowing which JSON-like things are not JSON at all.
Read guide →Is It Safe to Decode a JWT Online?
A JWT is readable by anyone who holds it, and pasting a live one into a website hands over a working credential. What that means in practice.
Read guide →What Is Base64, and When Should You Actually Use It?
Base64 turns binary data into text that survives systems built for text. It is not compression and it is not encryption — here is what it is for.
Read guide →What Is a SHA-256 Hash, and What Is It Actually For?
Hashes fingerprint data: same input, same output, and no way back. Where that is useful, where it is misused, and how to check a downloaded file.
Read guide →Are UUIDs Really Unique?
How random a version-4 UUID is, what the collision odds genuinely look like, and the cases where a UUID is the wrong identifier.
Read guide →Unix Timestamps Explained: Seconds, Milliseconds and Time Zones
How epoch time works, how to tell seconds from milliseconds at a glance, and the handful of mistakes that cause almost every date bug.
Read guide →Commas and Quotes in CSV: Why Your File Breaks and How to Fix It
CSV looks trivial until a field contains a comma, a quotation mark or a line break. The rules that actually apply, and how to spot a broken parse.
Read guide →URL Encoding Explained: When to Escape and What Breaks
Why spaces become %20, when a plus sign means a space, and the one rule that prevents most broken links and injected parameters.
Read guide →HEX, RGB and HSL: Which Colour Format to Use and When
The three ways to write a colour on the web, what the numbers mean, and why HSL is the one to reach for when you need to adjust a shade by hand.
Read guide →Regular Expressions for Everyday Tasks
The dozen pieces of regex syntax that cover almost every real job, the traps that cost hours, and a discipline for testing patterns before you trust them.
Read guide →Fast, free and privacy-focused
Digital Utility Kit is built around small tools that do one job well. Where browser technology allows it, processing happens locally on your device. No account is required to use these tools.