は言（い）うまでもない is a structure that combines the 副助詞（ふくじょし） (adverbial particle) は, the う - Verb 言（い）う, 2 additional 副助詞（ふくじょし） まで and も, and the
い-Adjective ない. This is regularly translated as ‘it goes without saying that (A)’, or ‘it is needless to say (A)’, where (A) is whatever comes before は.
This expression may be preceded by almost any phrase, but is often emphasized even further by the inclusion of こと (or の), or ということ (or の).
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彼（かれ）の成績（せいせき）がクラスで一番（いちばん）なのは言（い）うまでもない。
It goes without saying that his grades are the best in the whole class.
ガソリンの値段（ねだん）が上（あ）がれば、電気（でんき）自動車（じどうしゃ）の数（かず）が増（ふ）えることは言（い）うまでもない。
If the gas prices go up, it goes without saying that the amount of electric cars will increase.
師匠（ししょう）の戦（たたか）い方（かた）が凄（すご）いということは言（い）うまでもない。
It goes without saying how amazing the master’s fighting style is.
彼女（かのじょ）は歌（うた）うのが上手（うま）い。ピアノも言（い）うまでもない。
She is very good at singing. Needless to say, the piano too.
Literally, this expression is a combination of the meanings of its individual parts.
は - Presents the topic.
言（い）う - Presents that topic as something that can be said.
まで - Presents ‘being said’ as an extent.
も - Emphasizes the extent set by まで.
ない - Expresses that extent as not existing.
This grammar pattern will often be followed by structures such as が, to add a ‘but’ nuance.
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彼（かれ）の日本語（にほんご）がうまいのは言（い）うまでもないが、日本語（にほんご）が上手（うま）いのは日本（にほん）に30年（ねん）住（す）んているからである。
It goes without saying that his Japanese is very good, but he is good at Japanese because he has been living in Japan for 30 years.
一人（ひとり）で山（やま）を登（のぼ）るのが危（あぶ）ないというのは言（い）うまでもないが、気（き）をつけて行（い）けばそれほど危（あぶ）なくはない。
It goes without saying that it is dangerous to climb a mountain on your own, but if you go cautiously, it is not that dangerous.