End of Life Ruby 3.1 has reached end of life and gets no more fixes. Switch to Ruby 4.0 →

class method

Kconv.guess

Kconv.guess(str) => encoding

# File tmp/rubies/ruby-3.1.3/ext/nkf/lib/kconv.rb, line 141
def guess(str)
  ::NKF::guess(str)
end

Guess input encoding by NKF.guess

See also #guess .iseuc .isjis also in 3.3 · 3.2 · 3.0