Umlaut
In German, umlaut describes a vowel change represented in writing by two dots over a, o, or u. The resulting letters are ä, ö, and ü.
TWO DOTS, DIFFERENT FUNCTIONS
Umlaut vs. diaeresis
Umlaut and diaeresis can look identical. The difference is what the two dots do in a particular language and word.
Click a character, then paste with Ctrl+V or ⌘V.
CLEAR DEFINITION
The shape is the same, but the linguistic role differs
Diaeresis
A diaeresis commonly shows that a vowel is pronounced separately from a neighboring vowel, as in French Noël or naïve in English.
Neither label can be chosen from appearance alone. You need the language and the word. Other languages use the same two-dot characters as letters with their own alphabetic or pronunciation rules.
LANGUAGE EXAMPLES
How the two-dot letters are used
| Example | Language | Usual description | What the dots indicate |
|---|---|---|---|
| schön | German | Umlaut | An umlaut vowel, different from plain o |
| Müller | German | Umlaut | An umlaut vowel in a name |
| Noël | French | Diaeresis | The e is pronounced separately from o |
| naïve | English loanword | Diaeresis | The i begins a separate vowel sound |
| pingüino | Spanish | Diaeresis | The u is pronounced in the güi sequence |
| Örebro | Swedish | Alphabet letter | Ö is a distinct Swedish letter |
TECHNICAL IDENTITY
Why Unicode says “with diaeresis”
Unicode assigns stable character names for technical identification. Its names include LATIN SMALL LETTER A WITH DIAERESIS for ä and LATIN SMALL LETTER U WITH DIAERESIS for ü. Those names do not prevent the same characters from functioning as German umlaut letters.
The combining mark U+0308 is named COMBINING DIAERESIS, with double dot above and umlaut listed as alternative terminology. In ordinary text, use the precomposed character when one exists, such as ü at U+00FC. Copying from this page provides the precomposed form.
Do not change the character to change the label
German ü and Spanish ü share the same Unicode character. The language context determines whether the dots are called an umlaut or diaeresis, not a different code point.
Where to go next
COMMON QUESTIONS
Questions about umlaut and diaeresis
Are umlaut and diaeresis the same symbol?
They use the same two-dot shape and can use the same Unicode characters. The words describe different linguistic functions.
Is ë a German umlaut?
No. Standard German umlaut vowels are ä, ö, and ü. The dots on ë are generally described as a diaeresis in languages that use that character.
Is ü always an umlaut?
No. It is an umlaut letter in German, but Spanish uses ü as a diaeresis, and other languages assign the letter their own role.
Should I remove the dots if a word is still readable?
No. Preserve the original spelling. In German, use ae, oe, or ue only when a technical limitation prevents use of the umlaut character.
References: Unicode Combining Diacritical Marks names list, Unicode Latin-1 names list, and the Unicode Latin-script specification.