Grammar JLPT Level N3 - Lesson 11

～かは～によって違(ちが)う is an expression in Japanese that appears quite complex at first, but is actually quite simple when broken down into its parts. かは is a combination of the case marking particle か in its role as a quotation, paired with the adverbial particle は, highlighting the topic of the sentence. Together these can be translated as 'whether (A)'.
によって違(ちが)う is made up of the case marking particle に (highlighting a location), the て form of よる (a う - Verb), followed by 違(ちが)う 'to differ', (another う - Verb).
All together, this can be translated as '(A) depends on (B)'. More accurately though, the meaning is 'whether (A) will differ depending on (B)'. かは is regularly used after an entire phrase, followed by a noun and then によって違(ちが)う.

• 日本(にほん)が好(す)きか嫌(きら)いかは人(ひと)によって違(ちが)う。
  Whether they like Japan or not depends on the person.
• お酒(さけ)を飲(の)んで肌(はだ)が赤(あか)くなるかならないかは体質(たいしつ)によって違(ちが)う。
  Whether someone's skin will turn red or not after drinking depends on the person.
• 川(かわ)の流(なが)れが早(はや)いか遅(おそ)いかは場所(ばしょ)によって違(ちが)う。
  Whether the river flows fast or slow depends on the location.

Alternatively, かどうか may be used instead of かは. This changes the nuance from 'whether (A)', to 'whether or not (A)'. When translated directly, かどうか is quite similar to 'whether (A) or however'.

• 銃(じゅう)を簡単(かんたん)に買(か)えるかどうかは国(くに)によって違(ちが)う。
  Whether you can easily buy a gun or not depends on the country.
• この技(わざ)が凄(すご)いかどうかは見(み)る人(ひと)によって違(ちが)う。
  Whether this trick is amazing or not depends on who judges.

Finally, this expression may also be seen without 違(ちが)う. In a sentence like this, 'differs' is simply removed, becoming 'whether (A) will depend on (B)'. As conjugation between the verbs is no longer required, によって will become による.

• 今日(きょう)、早(はや)く帰(かえ)れるか帰(かえ)れないかは仕事(しごと)の進(すす)み具合(ぐあい)による。
  Whether I can go home early or not today will depend on how work goes.
• 納豆(なっとう)を食(た)べられるか食(た)べられないかは人(ひと)の好(この)みによる。
  Whether or not a person can eat natto will depend on what they like.