for all I know

for all (one) knows

Said when one is uncertain or has limited details about something. I haven't talked to Marie in weeks, so, for all I know, she's not even coming to the dinner party tonight.
See also: all, know
Farlex Dictionary of Idioms.

for all I know

according to the information I have; I think; probably. (Usually implies uncertainty.) For all I know, the mayor has resigned already. She may have gone to town for all I know.
See also: all, know
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.

for all I know

phr. as far as I know; I really don’t know. She came in late because she had an accident, for all I know.
See also: all, know
McGraw-Hill's Dictionary of American Slang and Colloquial Expressions
See also:
  • for all (one) knows
  • for all I, you, etc. know
  • for all someone knows
  • happen to
  • haul (something) from (something or some place)
  • scratch (one's) head
  • scratch one's head
  • scratch your head
  • Are you writing a book?
  • dialogue with