Security
Letters-Only Password Generator
Generate random passwords using only letters (A-Z, a-z). No digits, no symbols. For systems requiring alphabetic-only input. Free, browser-based, no signup.
About this letters-only password generator
Certain systems restrict passwords to letters only — no digits, no symbols. This is common in older mainframe environments, some educational platforms, and systems where the password must be spoken aloud (phone support verification codes, for example). With 52 possible characters (26 uppercase + 26 lowercase), each character contributes ~5.7 bits of entropy. A 16-character letters-only password provides ~91 bits of entropy — strong enough for most purposes. For maximum security within this constraint, always use both uppercase and lowercase letters and generate randomly rather than choosing words. This generator defaults to 16 characters with both cases enabled and all other character types disabled.
FAQ
Common questions
How long should a letters-only password be?
At least 16 characters to reach ~91 bits of entropy. If only one case is allowed (e.g., uppercase only), increase to 20+ characters to compensate for the reduced character set (26 vs 52 characters).
Is a letters-only password weaker than a mixed one?
Per character, yes — 5.7 bits vs 6.57 bits. But a 16-character letters-only password (~91 bits) is still stronger than a 12-character mixed password (~79 bits). Length compensates for character set limitations.
Why would a system restrict to letters only?
Phone verification codes meant to be spoken aloud, legacy mainframe systems, some educational platforms, and systems where special characters cause encoding issues in the underlying database.
Should I use uppercase and lowercase?
Always, if the system allows it. Using both cases doubles the character set from 26 to 52, adding ~1 bit of entropy per character. That is a significant improvement over the same length with one case.
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