Diceware Passphrase Generator
Generate 1–20 random words from EFF’s 7,776-word list and inspect the word count and estimated random bits.
About this diceware passphrase generator
Generate 1–20 random words from EFF’s 7,776-word list and inspect the word count and estimated random bits Runs entirely in-memory using Web Crypto primitives to keep sensitive tokens, certificates, and cryptographic keys secure from third-party interception.
Encoding & cryptographic principles
Selects each word independently from the 7,776-entry EFF large wordlist using crypto.getRandomValues. Rejection sampling removes modulo bias; words are joined with hyphens. Estimated random bits = n × log2(7776), rounded to one decimal.
Worked verification example
Scenario: Generate a six-word passphrase and inspect its word count and random-bit estimate.
Sample input:
Processing: In “Output”, check wordCount = 6, wordlistSize = 7776 and estimatedRandomBits = 77.5; the words may vary between runs.
Illustrative output:
Security parameters & input constraints
Enter a whole word count from 1 to 20 using ASCII digits; blank input defaults to 6. Fractions, signs, leading zeros and other formats are rejected. The browser must provide a cryptographic random source. Repeated words are allowed. Some EFF words contain a hyphen, so use the words array to identify word boundaries. The bit estimate assumes independent uniform selections; it is not a guarantee against attacks or device compromise.
Cryptographic digests, encoded strings, and signatures generated by Diceware Passphrase Generator should be verified against target authentication systems before production use.
Client-side Web Crypto boundary
Key derivation, hashing, and encoding in Diceware Passphrase Generator execute in local memory using Web Crypto APIs without remote socket transmission.
Cryptographic specifications & RFC standards
Technical specifications and cryptographic RFC standards governing algorithms and key representations:
- EFF Large Wordlist: 7776 entries
- Web Cryptography API: Crypto.getRandomValues
- Shannon entropy of independent uniform selections: n × log2(7776)
Diceware Passphrase Generator verification · Audit standards
How to use it
- Enter 6 in “Input”.
- Click “Run locally”.
- Click the action button or observe immediate live calculations rendered by Diceware Passphrase Generator.
Frequently asked questions
What input range does Diceware Generator accept?+
It accepts a whole-word count from 1 through 20. Empty input uses six words; an invalid count raises an input error instead of silently changing the request.
How are the selected words represented?+
The result JSON contains the requested wordCount, an EFF large-list words array, and a passphrase made by joining exactly those random words with hyphens.
What result should the documented example produce?+
With input 2 it returned two EFF-list words, a hyphen-joined matching passphrase, and a positive entropy estimate. The actual words are intentionally unpredictable.
Does estimated random bits guarantee a safe password?+
No. The estimate only derives from list size and word count. Safe use also depends on storing the passphrase, avoiding reuse, and the surrounding authentication system.