This article explains how to create an umlaut on Windows PC, Mac, and in HTML.

The umlaut diacritic, also called a diaeresis or trema, is formed by two small dots above a letter, in most cases a vowel. In the case of the lowercase i, these two dots replace the single dot. The umlaut diacritics appear on uppercase and lowercase vowels:

Many languages, including German, use umlauts. A few of these languages have loanwords in English, words that English has borrowed from the other language. For example, the French word naïf.

The umlaut diacritic mark is adopted into English when used in foreign branding, such as in advertising or for other special effects. The popular ice cream company Häagen-Daz illustrates such usage.