Test Data
Random Name Generator (First & Last Names by Country & Gender)
Generate realistic first and last names tailored to country origins, genders, and formats. Export instant clean CSV for mock databases and form autofill testing.
Open ToolRandom String Generator (Alphanumeric, Passwords & Secrets)
Generate cryptographically strong random strings, API secrets, and QA stress testing tokens with custom character sets and entropy calculations.
16 chars
k5[+E-l.u|vAZ^e+
⚡ Automated Token Injection
Automate Token Generation & Security Stress Testing
Generate cryptographically strong secrets, API keys, and edge-case test tokens, then pipe them directly into HTTP requests.
How to Generate Secure Random Strings
1
Configure Length & Rules
Adjust the slider between 4 and 128 characters and check uppercase, lowercase, numbers, or symbols.
2
Choose Ambiguity & Bulk Count
Optionally exclude ambiguous characters (0, O, l, 1) and select generation count up to 100 strings.
3
Copy or Download
Click Generate to produce strings with entropy rating. Copy single strings or download all as a .txt file.
Key Features of Random String Generator
Cryptographic Security
Uses window.crypto.getRandomValues for unbiased, cryptographically strong random generation.
Entropy Calculation
Displays real-time Shannon entropy in bits to evaluate brute-force resistance.
Exclude Ambiguous Chars
Omit visually confusing characters like 0/O and 1/l for clear human verification codes.
Bulk Export to TXT
Generate up to 100 strings per click and download cleanly formatted text files.
Shannon Entropy & Brute-Force Resistance Reference
Theoretical cracking resistance based on character pool size and bit entropy generated client-side by RunMacro CSPRNG.
| Length & Character Set | Pool Possibilities | Calculated Entropy | Recommended Use Case |
|---|---|---|---|
| 8 Chars (Lowercase + Numbers) | 36⁸ ≈ 2.82 × 10¹² | ~41.3 bits | Temporary OTPs & SMS verification codes |
| 16 Chars (Full Alphanumeric + Symbols) | 94¹⁶ ≈ 3.71 × 10³¹ | ~104.9 bits | Strong user account & master passwords |
| 32 Chars (Full Set) | 94³² ≈ 1.38 × 10⁶³ | ~209.7 bits | Production API tokens, Webhook HMAC secrets |
| 50 Chars (Full Set - Default UI) | 94⁵⁰ ≈ 4.79 × 10⁹⁸ | ~323.0 bits | Database salts, QA stress test input matrices |
Frequently Asked Questions
Clear answers about using this tool and automating workflows with RunMacro.
Are the generated strings sent to any server?
No. All strings and cryptographic tokens are generated 100% locally in your browser using the window.crypto.getRandomValues API. No data is transmitted or stored on RunMacro servers.
What is Shannon entropy and why does it matter?
Shannon entropy measures the unpredictability and information density of a generated string in bits. Higher entropy means exponential resistance against brute-force attacks and dictionary rainbow tables.
Can I use this for secure API keys and database salts?
Yes. Because the tool uses CSPRNG (Cryptographically Secure Pseudo-Random Number Generator), strings configured with 32+ characters and full character sets exceed 200 bits of entropy, making them ideal for production API keys, salts, and secret tokens.
How does RunMacro Web Automation integrate with random strings?
RunMacro Web Automation can iterate through generated token lists to automate user account provisioning, password reset testing, and API authentication flows across desktop and browser apps.
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