Classical Wilhelm-Baynes translation, three coin method, 64 hexagrams. No signup, no ads, free to use.
It also has an optional AI interpretation layer - but the classical text is always shown first, fully intact. Built it because I wanted something that treated the tradition seriously.
Carl Jung wrote the foreword to this exact translation and credited the I Ching with shaping his theory of synchronicity.
Also Terence McKenna said he used I Ching analysis/interpretation for his Timewave 2012 software and "Novelty Theory" or whatever his "the world is getting weirder and weirder" philosophy was called.