das Volumen
volume
The spatial capacity of a body; the amount of space that an object or substance occupies, measured in cubic units.
Das Volumen des Aquariums beträgt 200 Liter.
The volume of the aquarium is 200 liters.

volume
Loading your saved state.
volume
The spatial capacity of a body; the amount of space that an object or substance occupies, measured in cubic units.
Das Volumen des Aquariums beträgt 200 Liter.
The volume of the aquarium is 200 liters.

You can easily recognize the meaning of 'Volumen' (volume) from context. If it is about units of measurement like liters or cubic meters, it refers to spatial capacity. In the context of business and finance, it refers to quantity. With music or devices, it means loudness.
Das Handelsvolumen zwischen den beiden Ländern ist stark gewachsen.
The trade volume between the two countries has grown significantly.
In business and technology, 'Volumen' (volume) is often the second part of compound nouns. Important examples are 'das Handelsvolumen' (trade volume), 'Datenvolumen' (data volume), 'Marktvolumen' (market volume), or 'Auftragsvolumen' (order volume).
Mein Handyvertrag hat ein monatliches Datenvolumen von 10 Gigabyte.
My mobile phone contract has a monthly data volume of 10 gigabytes.
When 'Volumen' (volume) means loudness, it is often used with verbs like 'einstellen' (to set), 'regeln' (to adjust), 'erhöhen' (to increase), or 'reduzieren' (to reduce). Colloquially, people also say 'lauter' or 'leiser' stellen/machen (to turn up or turn down).
Kannst du das Volumen der Musik bitte etwas erhöhen?
Can you please turn up the volume of the music a little?
The meaning 'Buch' (book) is rare today and is considered formal or outdated. You mainly find it in library catalogs or in very old, multi-part works.
Das Lexikon umfasst zwanzig Volumen.
The encyclopedia comprises twenty volumes.
amount / crowd
'die Menge' and 'das Volumen' can both have to do with quantity. 'die Menge' is very general and only says how much of something is present. 'das Volumen' is more precise when it is about the space something takes up, for example a package, a container, or a liquid. In business or technology, 'Volumen' can also mean the scale or volume of data, trade, or production. Learners may confuse the words because both express 'how much'. But when it is about space, spatial capacity, or a more technical scale, 'Volumen' is more precise; in everyday language, 'Menge' is often the right choice.

Zu Hause messen wir das Volumen der Kiste für das Projekt.
At home, we are measuring the volume of the box for the project.
Wegen des Wetters kam nur eine kleine Menge Besucher zum Fest.
Because of the weather, only a small number of visitors came to the festival.