as far as I know
Used to qualify a statement based on the speaker's current knowledge. Often followed by a clause expressing what is known or believed.
See also: 知る限り
As far as I know, he is still in Japan.
To the best of my knowledge, that shop should have already closed.
Kana spelling of 限り; common in informal writing.
Phrase composed of 知っている (te-iru form of 知る 'to know') + 限り 'limit, as far as'. The combination expresses the extent of one's knowledge.