The modern Czech orthographic system is diacritic, having evolved from an earlier system which used many digraphs (although some digraphs have been kept - ch, d?). The caron is added to standard Latin letters to express sounds which are foreign to the Latin language. The acute accent is used for long vowels.
The Czech orthography is considered the model for many other Slavic languages using the Latin alphabet; Slovak orthography being its direct revised descendant, while the Croatian Gaj's Latin alphabet and its Slovene alphabet descendant system are largely based on it. All of them make use of similar diacritics and also have a similar, usually interchangeable, relationship between the letters and the sounds they are meant to represent.
The Czech alphabet consists of 42 letters.
|Majuscule forms (also called uppercase or capital letters)|
|Minuscule forms (also called lowercase or small letters)|
The letters Q, W and X are used exclusively in foreign words, and the former two are replaced with Kv and V once the word becomes "naturalized"; the digraphs dz and d? are also used mostly for foreign words and do not have a separate place in the alphabet.
Czech orthography is primarily phonemic (rather than phonetic) because an individual grapheme usually corresponds to an individual phoneme (rather than a sound). However, some graphemes and letter groups are remnants of historical phonemes which were used in the past but have since merged with other phonemes. Some changes in the phonology have not been reflected in the orthography.
|?||, /j?/||Marks palatalization of preceding consonant; see usage rules below|
|i||Palatalizes preceding ⟨d⟩, ⟨t⟩, or ⟨n⟩; see usage rules below|
|í||Palatalizes preceding ⟨d⟩, ⟨t⟩, or ⟨n⟩; see usage rules below|
|ó||Occurs mostly in words of foreign origin.|
|ú||See usage rules below|
|?||See usage rules below|
|y||See usage rules below|
|ý||See usage rules below|
|d||Represents before ⟨i í ?⟩; see below|
|f||Occurs mostly in words of foreign origin.|
|g||Occurs mostly in words of foreign origin.|
|n||Represents before ⟨i í ?⟩; see below|
|t||Represents before ⟨i í ?⟩; see below|
|x||/ks/, /gz/||Occurs only in words of foreign origin; pronounced /?z/ in words with the prefix 'ex-' before vowels or voiced consonants.|
All the obstruent consonants are subject to voicing (before voiced obstruents except ⟨v⟩) or devoicing (before voiceless consonants and at the end of words); spelling in these cases is morphophonemic (i.e. the morpheme has the same spelling as before a vowel). An exception is the cluster ⟨sh⟩, in which the /s/ is voiced to /z/ only in Moravian dialects, while in Bohemia the /?/ is devoiced to /x/ instead (e.g. shodit /sxot/, in Moravia /z?ot/). Devoicing /?/ changes its articulation place: it becomes [x]. After unvoiced consonants ⟨?⟩ is devoiced: for instance, in t?i 'three', which is pronounced . Written voiced or voiceless counterparts are kept according to the etymology of the word, e.g. odpadnout ['otpadnot] (to fall away) - od- is a prefix; written /d/ is devoiced here because of the following voiceless /p/.
For historical reasons, the consonant [?] is written k in Czech words like kde ('where', < Proto-Slavic *k?d?) or kdo ('who', < Proto-Slavic *k?to). This is because the letter g was historically used for the consonant [j]. The original Slavic phoneme /?/ changed into /h/ in the Old-Czech period. Thus, /?/ is not a separate phoneme (with a corresponding grapheme) in words of domestic origin; it occurs only in foreign words (e.g. graf, gram, etc.).
The letters ?i? and ?y? are both pronounced [?], while ?í? and ?ý? are both pronounced [i:]. ?y? was originally pronounced [?] as in contemporary Polish. However, in the 14th century, this difference in standard pronunciation disappeared, though it has been preserved in some Moravian dialects. In words of native origin "soft" ?i? and ?í? cannot follow "hard" consonants, while "hard" ?y? and ?ý? cannot follow "soft" consonants; "neutral" consonants can be followed by either vowel:
|Soft||?, ?, ?, ?, c, j, ?, ?, ?|
|Neutral||b, f, l, m, p, s, v, z|
|Hard||h, ch, k, r, d, t, n, g|
When ?i? or ?í? is written after ?d, t, n? in native words, these consonants are soft, as if they were written , ?, . That is, the sounds [, ?i:, c?, ci:, , ?i:] are written ?di, dí, ti, tí, ni, ní? instead of i, ?í, ?i, ?í, ?i, ?í?, e.g. in ?e?tina ['t?c?na]. The sounds [d?, di:, t?, ti:, n?, ni:] are denoted, respectively, by ?dy, dý, ty, tý, ny, ný?. In words of foreign origin, ?di, ti, ni? are pronounced [d?, t?, n?]; that is, as if they were written ?dy, ty, ny?, e.g. in diktát, dictation.
Historically the letter ?c? was hard, but this changed in the 19th century. However, in some words it is still followed by the letter ?y?: tác (plate) - tácy (plates).
Because neutral consonants can be followed by either ?i? or ?y?, in some cases they distinguish homophones, e.g. být (to be) vs. bít (to beat), mýt (to wash) vs. mít (to have). At school pupils must memorize word roots and prefixes where ?y? is written; ?i? is written in other cases. Writing ?i? or ?y? in endings is dependent on the declension patterns.
The letter is a vestige of Old Czech palatalization. The originally palatalizing phoneme /?/  became extinct, changing to [?] or [j?], but it is preserved as a grapheme which can never appear in the initial position.
There are two ways in Czech to write long [u:]ú? and . cannot occur in an initial position, while ?ú? occurs almost exclusively in the initial position or at the beginning of a word root in a compound.
Historically, long ?ú? changed into the diphthong ?ou? [ou?] (as also happened in the English Great Vowel Shift with words such as "house"), though not in word-initial position in the prestige form. In 1848 ?ou? at the beginning of word-roots was changed into ?ú? in words like ou?ad to reflect this. Thus, the letter ?ú? is written at the beginning of word-roots only: úhel (angle), trojúhelník (triangle), except in loanwords: skútr (scooter).
Meanwhile, historical long ?ó? [o:] changed into the diphthong ?uo? [?o]. As was common with scribal abbreviations, the letter ?o? in the diphthong was sometimes written as a ring above the letter ?u?, producing , e.g. kó? > kuo? > k (horse), like the origin of the German umlaut. Later, the pronunciation changed into [u:], but the grapheme has remained. It never occurs at the beginning of words: d?m (house), dom? (home, homeward).
The letter now has the same pronunciation as the letter ?ú? (long [u:]), but alternates with a short ?o? when a word is inflected (e.g. nom. k -> gen. kon?, nom. d?m -> gen. domu), thus showing the historical evolution of the language.
The predicate must be always in accordance with the subject in the sentence - in number and person (personal pronouns), and with past and passive participles also in gender. This grammatical principle affects the orthography (see also "Soft" I and "Hard" Y) - it is especially important for the correct choice and writing of plural endings of the participles.
|masculine animate||pes byl koupen||psi byli koupeni||a dog was bought/dogs were bought|
|masculine inanimate||hrad byl koupen||hrady byly koupeny||a castle was bought/castles were bought|
|feminine||ko?ka byla koupena||ko?ky byly koupeny||a cat was bought/cats were bought|
|neuter||m?sto bylo koupeno||m?sta byla koupena||a town was bought/towns were bought|
The mentioned example shows both past (byl, byla ...) and passive (koupen, koupena ...) participles. The accordance in gender takes effect in the past tense and the passive voice, not in the present and future tenses in active voice.
If the complex subject is a combination of nouns of different genders, masculine animate gender is prior to others and the masculine inanimate and feminine genders are prior to the neuter gender.
Priority of genders:
The use of the full stop (.), the colon (:), the semicolon (;), the question mark (?) and the exclamation mark (!) is similar to their use in other European languages. The full stop is placed after a number if it stands for ordinal numerals (as in German), e.g. 1. den (= první den) - the 1st day.
The comma is used to separate individual parts in complex-compound sentences, lists, isolated parts of sentences, etc. Its use in Czech is different from English. Subordinate (dependent) clauses must be always separated from their principal (independent) clauses, for instance. A comma is not placed before a (and), i (as well as), ani (nor) and nebo (or) when they connect parts of sentences or clauses in copulative conjunctions (on a same level). It must be placed in non-copulative conjunctions (consequence, emphasis, exclusion, etc.). A comma can, however, occur in front of the word a (and) if the former is part of comma-delimited parenthesis: Jakub, m?j mlad?í bratr, a jeho u?itel Filip byli p?íli? zabráni do rozhovoru. Probírali látku, která bude u zkou?ky, a té?, kdo na ní bude. A comma also separates subordinate conjunctions introduced by compostide conjunctions a proto (and therefore) and a tak (and so).
Quotation marks. The first one preceding the quoted text is placed to the bottom line:
Other types of quotation marks: ,' »«
Apostrophes are used rarely in Czech. They can denote a missing sound in non-standard speech, but it is optional, e.g. ?ek' or ?ek (= ?ekl, he said).
The first word of every sentence and all proper names are capitalized. Special cases are:
In the 9th century, Glagolitic script was used, during the 11th century it was replaced by Latin script. There are five periods in the development of the Czech Latin-based orthographic system:
In computing, several different coding standards have existed for this alphabet, among them: