One-Time Password Generator

About This Tool

The tool generates one-time passwords (OTPs) by selecting characters from a user-defined alphabet. It accepts inputs for length and character classes (uppercase, lowercase, digits, symbols) and can apply exclusions to avoid ambiguous characters. Conceptually, the process builds a pool of allowed characters, then samples from that pool using a cryptographically secure random number generator to produce a code of the requested length. This approach ensures high entropy and unpredictability, suitable for temporary authentication codes used in MFA flows or testing environments. The generator can operate with or without a seed. When a seed is provided, the output is reproducible, which is valuable for automated test scenarios or reproducible QA runs. The tool is especially beneficial for developers and security teams who require repeatable OTP generation in scripts, CI pipelines, or security audits, while maintaining strong randomness guarantees. Unique differentiators include explicit support for exclusions of similar-looking characters, optional repetition rules, and the option to lock entropy through a seed for deterministic testing, all without requiring any persistent storage or network calls. Typical use cases include validating login flows in staging environments, scripting OTP creation for automated access tests, and auditing the behavior of MFA integrations with realistic, high-entropy codes. Core capabilities emphasize reliability, cryptographic strength, and flexibility for integration into diverse workflows.

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