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Random String Generator

Generate secure random strings for passwords, tokens, and testing

Tips for Generating Random Strings

Build strings that are both secure and usable:

• Include All Character Types for Passwords: A password with only lowercase letters is weak regardless of length. Check uppercase, numbers, and special characters to maximize entropy per character.
• Exclude Similar Characters for User-Facing Codes: Characters like 0/O and l/1/I are easily confused. If humans will read or type the string (coupon codes, license keys), toggle the ambiguous character exclusion option.
• Length Matters More Than Complexity: A 20-character lowercase-only string is stronger than an 8-character string with all symbols. When in doubt, increase length first, then add character variety.
• Generate Batches for Testing: Need 50 API keys for a load test? Set quantity to 50 and generate them all at once. Use the "Copy All" button to grab the list.

How to Choose Character Types

The character sets you pick directly affect both security and usability:

• Passwords & secrets: Check all four boxes (uppercase, lowercase, numbers, symbols). At 16+ characters, this creates strings that are effectively unguessable.
• API keys & tokens: Uppercase + lowercase + numbers (no symbols) gives you 62 possible characters per position. This is the standard for Stripe, GitHub, and most API key formats.
• User-facing codes: Uppercase + numbers only — and consider excluding ambiguous characters. A 6-character code from 28 unambiguous characters is still ~480 million combinations, enough for email verification.
• Filenames & IDs: Lowercase + numbers only. Avoids case-sensitivity issues across Windows/Mac/Linux and makes the string URL-safe.