How many six-word combinations are possible?
Six independently selected EFF words create 221,073,919,720,733,357,899,776 possible ordered passphrases, equal to an estimated 77.55 bits.
Scope: the calculation assumes every word is selected randomly and independently. A passphrase chosen by a person can be much easier to guess.
How many combinations does a random passphrase have?
Four random EFF words create 3,656,158,440,062,976 combinations. Six words create 221,073,919,720,733,357,899,776, while eight words create 13,367,494,538,843,734,067,838,845,976,576.
| Words | Exact combinations | Estimated bits |
|---|---|---|
| 4 | 3,656,158,440,062,976 | 51.70 |
| 5 | 28,430,288,029,929,701,376 | 64.62 |
| 6 | 221,073,919,720,733,357,899,776 | 77.55 |
| 8 | 13,367,494,538,843,734,067,838,845,976,576 | 103.40 |
How long are the words in the EFF list?
The average word is 6.99 characters long, the median is 7.0, and every word falls between 3 and 9 characters. We checked every word in the list, not a sample.
- Total
- 7,776 words
- Average
- 6.99 characters
- Median
- 7.0 characters
- Range
- 3–9 characters
How did we calculate these figures?
We keep combination totals as exact whole numbers. When a report includes time estimates, we keep them as exact fractions of a second and use 31,557,600 seconds per year for the readable versions. Entropy estimates use log2(number of possible outcomes) and assume every choice is random and equally likely. The source file contains 7,776 unique entries with SHA-256 addd35536511597a02fa0a9ff1e5284677b8883b83e986e43f15a3db996b903e. Possible combinations are 7776^W.
These are mathematical comparisons, not measurements from real attacks or specific hardware.
Where do the word list and figures come from?
- Electronic Frontier Foundation, Dice-Generated Passphrases — EFF's guide to making passphrases with dice.
- EFF Long Wordlist for Passphrases — the full 7,776-word list used for this report.
- NIST SP 800-63B-4, Appendix A: Strength of Passwords — explains why random selection is different from choosing words yourself.
- Release 1 data and calculation details — the word counts, formulas, checksums, and full set of results.
EFF provides the word list and dice codes. We used that list to calculate the totals, entropy estimates, and word-length figures shown here.
These estimates assume each word is picked at random from the full list, with every word equally likely. A passphrase someone invents will not follow the same math. We also do not count a fixed separator or capitalization pattern as extra randomness.
EFF list retrieved 2026-09-23 and verified against SHA-256 addd35536511597a02fa0a9ff1e5284677b8883b83e986e43f15a3db996b903e. NIST source reviewed 2026-10-21.
Can you download or cite this data?
Yes. Download the complete release, the passphrase combinations, or the word-length counts.
Suggested citation: “Generate My Password, Passphrase Security Statistics, release password-statistics-release-1-v1 (2026-10-21).”
Related statistics
Compare random password length and search space, inspect the fixed-rate guessing-time estimates, browse the EFF word list, or generate a Diceware passphrase.