Translation guide
The English word 'length' covers physical measurement, duration, and extent. Japanese uses different words depending on what is being measured.
The measurement of something from end to end, like a rope, table, or road.
General word for physical length. Used for objects, distances, and abstract lengths.
このロープの長さは5メートルです。
The length of this rope is 5 meters.
机の長さを測ってください。
Please measure the length of the desk.
Overall length, total length. Often used for vehicles, animals, or large objects.
この車の全長は4.5メートルです。
The overall length of this car is 4.5 meters.
Length of clothing, especially for kimono or pants. Also used for height of a person (archaic).
着物の丈を直してもらいました。
I had the length of the kimono altered.
How long something lasts, like a movie, meeting, or trip.
Also used for duration, though slightly less common than for physical length. Natural in many contexts.
映画の長さは2時間です。
The length of the movie is 2 hours.
Literally 'time', but often used where English says 'length' for durations. More common in speech.
Pattern: [event] + の長さ. Works for both physical and temporal length.
旅行の長さは1週間です。
The length of the trip is one week.
The extent of a text, document, or spoken content.
Works for any kind of content length.
レポートの長さは10ページです。
The length of the report is 10 pages.
Refers to quantity or volume of writing, often used for books, articles, or homework.
Duration of a phonetic segment in linguistics or language learning.
Used in phonetics.
日本語では母音の長さが意味を変えることがあります。
In Japanese, vowel length can change the meaning.
The phrase 'at length' meaning thoroughly or after a long time.
Means 'in detail'. Used when 'at length' means thoroughly.
彼はその問題について詳しく話した。
He spoke at length about the problem.
Means 'at great length', often with a nuance of being too long or tedious.
彼は長々とスピーチをした。
He gave a speech at length (and it was long-winded).
Means 'finally' or 'at last'. Used when 'at length' means after a long time.
やっと彼が到着した。
At length, he arrived.
To make a lot of effort to achieve something.
Literally 'make every effort'. Natural equivalent.
彼は成功するためにあらゆる努力をした。
He went to great lengths to succeed.
Means 'spare no effort/trouble'. Emphasizes not hesitating to take time and effort.
彼女は手間を惜しまずに料理を作った。
She went to great lengths to prepare the meal.
長さ only refers to length (the longest dimension). For height use 高さ (たかさ), for width use 幅 (はば).
Both can express duration, but 時間 is more common in everyday questions like 'How long is the meeting?' (会議の時間はどのくらいですか？). 長さ sounds slightly more formal or written.
その橋の長さは300メートルです。
The length of the bridge is 300 meters.
彼女は状況を詳しく説明した。
She explained the situation at length.
What is the length of the meeting? (How long is the meeting?)
この本は分量が多い。
This book is long (has a lot of content).