Hungarian Umlauts Cheatsheet

Hungarian has fourteen vowels, and length is phonemic throughout — meaning a long vowel and its short counterpart are different sounds that distinguish different words. The two characters that make Hungarian visually distinctive are ő and ű, carrying what is called the double acute or hosszú kettős ékezet. They are the long counterparts of ö and ü, and they exist in essentially no other language, which is why fonts and systems that handle German umlauts perfectly will sometimes fail on Hungarian.

That failure has a specific and very common symptom. When a font lacks ő and ű, or when software substitutes carelessly, the double acute gets replaced by a tilde or a circumflex, so Erdős becomes Erdõs and űr becomes ûr. This substitution is so widespread in older Hungarian computing that it has a name among Hungarian users, and it is the single most reliable sign that a document has passed through a system with poor Hungarian support. If you are correcting text, õ and û in Hungarian are almost always ő and ű that have been damaged.

Vowel length changes meaning in ordinary vocabulary, not just in edge cases. Törik means it breaks; tőrik would be a different form entirely. Kor is age, kór is disease. Örül means to be glad, őrül means to go mad. Because Hungarian is agglutinative and piles suffixes onto stems, a wrong vowel length also propagates through every inflected form of the word, so a single mistyped ő can make a whole paragraph read oddly to a native speaker.

Hungarian vowel harmony makes the distinction structural rather than incidental. Suffixes come in front and back variants and must match the vowels of the stem, so the vowels in a word are not independent choices. This is part of why Hungarian writing tolerates so little diacritic sloppiness: the vowels carry grammatical information, and stripping the marks removes it.

On Windows, hold Alt with Num Lock on: ő is Alt+0245 and ű is Alt+0251 in the Central European codepage, with ö at Alt+0246 and ü at Alt+0252. Codepage dependence makes these unreliable in some applications, so the Hungarian layout is the better answer — it places ö, ü, ő and ű on dedicated keys around the right-hand side of the keyboard. On macOS, hold the o or u key to open the accent picker, which includes the double-acute forms, or use Option+G followed by the vowel on a Hungarian input source. On Linux, Compose then = then the vowel gives the double acute. On mobile, long-press o or u and look past the umlaut to the double-acute entry, which sits further along the popup and is easy to miss.