Generate UUIDs, QR codes, and various content
Generate unique identifiers (UUID/GUID) with customizable formats
Generate placeholder text with multiple styles and HTML format
Generate custom QR codes for text, URL, WiFi, vCard, email, SMS and more
Generate professional barcodes in Code128, EAN-13, UPC-A, Code39 and more formats
Build, validate and explain cron expressions with visual interface
Convert colors between HEX, RGB, HSL, CMYK, YCbCr, Lab formats, generate color palettes, and check WCAG contrast
Professional color palette generator with color mixing, gradient creation, color schemes, and export to CSS/SCSS/JSON formats
Generate strong, secure random passwords with customizable length, character types, strength indicator, and batch generation
Calculate days between dates, add/subtract days, calculate age, and count business days
Generate realistic test data including names, emails, phones, addresses. Supports 12 locales and multiple output formats
Data generation and random content creation are essential for development, testing, and data population tasks. This category covers tools for generating UUIDs following RFC 4122 standards, creating secure random passwords following OWASP guidelines, generating cron expressions for task scheduling, QR codes for contact information and URLs, and fake data for testing and demonstration purposes. These generators are critical for database seeding, API testing, security testing, and rapid prototyping. Understanding UUID versions, password generation entropy, cron syntax, and QR code specifications ensures you generate correct and secure data for your use cases. This guide covers generation standards, security best practices, and troubleshooting common generation errors.
Generate universally unique identifiers following RFC 4122 standards. UUID v4 (random) is recommended for most use cases, UUID v1 for timestamp-based identification.
Create cryptographically secure random passwords following OWASP guidelines. Customize length, character sets, and complexity requirements for different security levels.
Generate QR codes from text, URLs, or contact information. Configurable error correction levels for reliability in various environments.
| Generator Type | Features & Use Cases |
|---|---|
| UUID Generator | Creates globally unique identifiers. UUID v1: timestamp-based, predictable. UUID v4: random, recommended for security. UUID v5: SHA-1 hash-based, deterministic. |
| Password Generator | Generates cryptographically secure passwords. OWASP recommends 12+ characters mixing uppercase, lowercase, numbers, symbols. Entropy: 4-6 bits per character. |
| QR Code Generator | Creates scannable 2D barcodes from URLs and text. Error correction: L(7%), M(15%), Q(25%), H(30%). Larger error correction = larger QR code. |
| Cron Generator | Creates cron expressions for task scheduling. Supports five-field format (minute, hour, day, month, weekday). Essential for Linux cron jobs and CI/CD pipelines. |
| Fake Data Generator | Generates realistic test data: names, addresses, emails, phone numbers, credit card (fake). Useful for database seeding and testing without real PII. |
| Lorem Ipsum Generator | Generates placeholder text for design mockups and content templates. Available in words, sentences, or paragraphs. |
Use UUID v4 (random) for most applications. UUID v1 for timestamp tracking. Never use simple incrementing IDs in distributed systems. Validate UUID format before storing.
Use 12+ character passwords with mixed character types. Avoid dictionary words and predictable patterns. Use bcrypt/Argon2 for hashing, never store plaintext. Rotate regularly.
L (7% recovery): clean environments, Q (25%): outdoor/printed, H (30%): damaged/worn. Higher correction level = larger QR code size.
Test cron expressions before deployment. Use online validators. Remember: minute hour day month weekday (* = all, ? = any). Document complex expressions for team understanding.
Use established fake data generators (Faker.js, Python Faker) instead of writing custom ones. Ensures realistic data and consistent formats.
Clearly separate test data from production systems. Never expose fake credit cards, emails, or PII externally. Use namespacing or database isolation for test data.