Password Generator and Analyzer

Password Generator and Analyzer

The /generator page is a standalone, 100% client-side password lab with two tabs: a Generator and an Analyzer. Nothing you generate or paste is ever stored or transmitted. Settings are shared with the home-page key-generator popover via the same localStorage preferences.

Generator tab

Generate cryptographically secure keys using the Web Crypto API (crypto.getRandomValues) with rejection sampling to eliminate modulo bias, so the output is perfectly uniform.

Seven key types:

Mode	Description
Unicode	CJK + emoji + symbols (maximum entropy per character)
Secure	Latin letters + symbols + accents
Alphanumeric	letters and digits
Hex	hexadecimal token
Base58 (readable)	Bitcoin alphabet, excludes 0 O I l — safe to dictate or hand-copy
PIN	digits only
UUID v7	time-ordered UUID

Controls:

• Length — a stop-slider with presets from 16 to 1024, plus a custom input up to 2048 characters.
• Quantity — generate 1 to 50 keys at once (default 1).
• Advanced options (persisted in preferences): exclude ambiguous characters (0O1lI), exclude custom characters, guarantee all character classes, no consecutive repeats, group with dashes every 4/6/8.

Every generated key is scored and sorted strongest → weakest, with per-key copy, copy-all, and download as .txt.

Analyzer tab

Paste any password for a live report:

• Effective entropy — estimated from the character classes present (lowercase, uppercase, digits, symbols, unicode): log2(pool) × length, then penalized for structural weaknesses (leaked-list matches, repeated blocks, sequences, keyboard patterns, embedded years).
• Four attack scenarios — crack times at 10², 10⁶, 10¹², and 10¹⁵ guesses/second.
• Cybersecurity framework checks — NIST SP 800-63B, OWASP (≥64 bits), long-term (≥100 bits), AES-128 (≥128 bits), and post-quantum (Grover) thresholds.
• Total keyspace and post-quantum entropy.
• Comparison vs. an average human password (~40 bits).
• Plain-language tooltips for every metric (es / en / pt).

Beyond the browser

The same engine is available as zefer keygen / zefer analyze in the CLI, as the zefer_keygen / zefer_analyze_password tools in the MCP Server, and as generateWithOptions / analyzePassword in the Library.

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📖 Glossary — terms on this page: entropy · brute force · symmetric key · post-quantum · hash (SHA-256). Full list in the Glossary.