Karelian alphabet are from the ISO basic Latin alphabet, five are derived from basic Latin letters by the addition of diacritical marks, and the final character is the apostrophe, which signifies palatalization of the preceding sound. The entire range of sounds of native Karelian words is intended to be represented by this set of characters. This unified alphabet was approved in 2007 as a replacement for the separate Olonets Karelian and Karelian Proper alphabets. The letters Ä and Ö are vowels which, unlike the German umlauts, are considered to be distinct and are alphabetized separately from the corresponding vowels without the umlauts.
Cardinal vowels the opposite side of the front-back dimension, so that e.g. Cardinal 1 can be produced with rounding somewhat similar to that of Cardinal 8 (though normally compressed rather than protruded); these are known as 'secondary cardinal vowels'. Sounds such as these are claimed to be less common in the world's languages. Other vowel sounds are also recognised on the vowel chart of the International Phonetic Alphabet. In the , the cardinal vowels have the same numbers used above, but added to 300. The usual explanation of the cardinal vowel system implies that the competent user can reliably distinguish between sixteen