I'd like to make a password generator - strictly for myself. I'd like four "levels" of characters, but I'm a bit unsure of which symbols should be in each of the three latter ones - since I don't know which symbols sites are likely to disallow. I know this is somewhat a question of "personal opinion" - but let's call it "experience" instead...
I'm not going to use any accented letters, letters from other alphabets (Greek, Cyrillic, ...), letters only used in a few countries (like letters specific to Scandinavia or Poland), or special symbols (like "masculine" or "upside-down question mark"). So please ignore these...
My four "levels":
- Upper-and lower-case letters, and digits
- Symbols, "always" allowed (if the site accept symbols in passwords, it accepts these)
- Symbols "usually" allowed (if the site allows more than the very minimal of symbols, it allows these too)
- Symbols "sometimes" forbidden (in the rare case some symbols are not allowed, it's usually some of these)
(...And while not applicable to my password-generator, are there any symbols that are almost always forbidden for various reasons?)