Generate secure random strings, passwords and API keys with entropy shown.
Strong password
Mixed sets at a sensible length
20API key
Long alphanumeric string
40Short code
Unambiguous characters for reading aloud
8Lowercase, uppercase, digits and symbols can be combined freely. More sets mean more entropy per character.
Length contributes more to strength than complexity does. Twenty characters of mixed case and digits is very strong.
Check the entropy figure, then copy. Generate a fresh value rather than reusing one across services.
Values come from the browser’s cryptographic generator, using rejection sampling so no character is more likely than another.
Bits of entropy tell you how hard a string is to guess. Vague strength meters do not, and often mislead.
Excluding O, 0, l, 1 and I matters whenever a code will be read aloud, printed, or typed from a screenshot.
Generate random strings using your browser’s cryptographic random number generator — never Math.random, which is predictable and unsuitable for anything that needs to be unguessable. Choose which character sets to include, set the length, and optionally exclude characters that are easy to confuse when read aloud or printed. The entropy of your current settings is shown in bits, which is the only honest measure of how hard a string is to guess.
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