Je voudrais vs je veux to say that you want something in French

In French, you can use "je voudrais" and "je veux" to say that you want something. There is still a difference as to which to use.

When to use 'je voudrais' and 'je veux' in French

Look at these examples:

Note that to ask for something in French, you could use two forms of the verb vouloir: 
je veux (I want) or je voudrais (I would want/like)

Je voudrais is preferable in social contexts such as in a restaurant, as it is more polite and subtle than the blunt je veux (just like in English).

[Note that j'aimerais (I would like) is also very commonly used in more polite contexts.]

Grammar point: Je veux is in Le Présent tense (I want), whereas je voudrais is in Le Conditionnel (I would want/like).