Estonian orthography

Estonian orthography is the system used for writing the Estonian language and is based on the Latin alphabet. The Estonian orthography is generally guided by phonemic principles, with each grapheme corresponding to one phoneme.

Due to German influence, the Estonian alphabet (Estonian: eesti tähestik) has the letters Ä, Ö, and Ü (A, O, and U with umlaut), which represent the vowel sounds [æ], [ø] and [y], respectively. Unlike the German umlauts, they are considered and alphabetised as separate letters and are part of the alphabet. The most distinctive letter in the Estonian alphabet, however, is the Õ (O with tilde), which was added to the alphabet in the 19th century by Otto Wilhelm Masing and stands for the vowel [ɤ]. In addition, the alphabet also differs from the Latin alphabet by the addition of the letters Š and Ž (S and Z with caron/háček), and by the position of Z in the alphabet: it has been moved from the end to between S and T (or Š and Ž).

The official Estonian alphabet has 27 letters: A, B, D, E, F, G, H, I, J, K, L, M, N, O, P, R, S, Š, Z, Ž, T, U, V, Õ, Ä, Ö, Ü. The letters F, Š, Z, Ž are so-called "foreign letters" (võõrtähed), and occur only in loanwords and foreign proper names. Occasionally, the alphabet is recited without them, and thus has only 23 letters: A, B, D, E, G, H, I, J, K, L, M, N, O, P, R, S, T, U, V, Õ, Ä, Ö, Ü.

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