// private-by-design developer utilities

Examples & tiny tools
for people who ship.

Practical utilities and copy-paste examples for the web. Tool input is processed locally in your browser.

explore tools →

local://privacy-check

$ inspect data-flow

✓ all processing runs locally in your browser

$_

// toolkit

Useful in a pinch.

Fast tools for everyday debugging, encoding and security work.

{ }format

JSON Formatter

Format, minify and validate JSON without uploading it.

open tool → ◇security

JWT Decoder

Inspect token headers and payloads. Decode only — never verify.

open tool → %_encode

URL Encoder

Encode and decode URL components safely.

open tool → 64encode

Base64

Encode text to Base64 or decode it back to UTF-8.

open tool → ⌚time

Unix Timestamp

Convert timestamps to readable dates and back.

open tool → #crypto

SHA-256

Create a SHA-256 hash with the Web Crypto API.

open tool → ◎generate

UUID Generator

Generate secure UUID v4 values instantly.

open tool → <encode

HTML Escape

Escape text for HTML or turn entities back into text.

open tool → .*test

Regex Tester

Test JavaScript regular expressions with live matches.

open tool → ⛨security

CSP Generator

Build a minimal Content-Security-Policy header.

open tool → * * *reference

Cron Expression

Explain standard five-field cron expressions.

open tool → •••security

Password Strength

Estimate password entropy locally, with no storage.

open tool → H:examples

HTTP Header Examples

Practical security, caching and API header examples.

view examples → ▣generate

QR Code Generator

Create a customizable QR code and save it as a PNG.

open tool → +81parse

Phone Number Parser

Validate and format international telephone numbers locally.

open tool → =>encode

ArrowFxxk Generator

Generate JavaScript character expressions with arrow functions.

open tool → 人generate

Japanese Fake Profile

Generate a plausible synthetic Japanese profile for testing and mockups.

open tool → ▦arcade

Color Puzzle Arcade

Play four colorful puzzle games directly in your browser.

play games →

// transparent by design

Built for the workbench.

examplu is an independent collection of small, focused developer tools. Tool input is processed in your browser. The site uses third-party advertising; details are available in the privacy policy.