Case Converter

Paste your text and read the Title Case card. It shows AP, APA, Chicago and Español (RAE) on separate rows at the same time, so you can copy the one your style guide uses without switching anything.

Mostly word length. APA lowercases minor words of three letters or fewer. AP lowercases prepositions and conjunctions of three letters or fewer, but always capitalizes the first and last word. Chicago lowercases prepositions of four letters or fewer, so a four-letter word like with or from is lowercase in Chicago and capitalized in AP.

In AP and Chicago, yes — a short word is capitalized when it is first or last. APA has no such rule: its published list of what to capitalize covers the first word, the first word of a subtitle, major words and words of four letters or more, and says nothing about the last word. So What Are You Waiting for keeps a lowercase for in APA and takes a capital For in AP.

Capitalize the first word only. The Ortografía de la lengua española states that only the first word of a title takes an initial capital, with proper nouns as the exception, and gives Diccionario de la lengua española as correct against Diccionario de la Lengua Española as incorrect. The Español (RAE) row applies exactly that rule.

The Chicago Manual of Style lowercased prepositions regardless of length from its 12th edition in 1969 until its 17th. The 18th edition, published in 2024, capitalizes prepositions of more than four letters, which is why The Gospel according to Matthew is now styled The Gospel According to Matthew. A tool built against the older rule gives a different answer.

The table on this page lists the common ones and marks which of the three English styles lowercases each. The styles agree on articles and short conjunctions and disagree on four-letter prepositions such as from, into, over, past, upon and with.

Sentence case capitalizes only the first letter of each sentence, like ordinary prose. It is the default for body text and for most modern interface style guides, which is why many publications now prefer it to title case for headings.

Yes. A word you typed entirely in capitals with two or more letters — NASA, HTML, IV — is kept as typed through Title Case, sentence case and Capitalize Each Word. The exception is text that is entirely in capitals, where there is no way to tell an acronym from shouting, so everything is converted.

Yes. Every case is Unicode-aware, so época becomes Época rather than éPoca, and ñ alternates correctly in aLtErNaTiNg. The one place accents are deliberately removed is kebab-case, because a URL slug is conventionally plain ASCII; snake_case, camelCase and the rest keep them.

camelCase joins words with no separator and capitalizes each word after the first (myVariableName). snake_case joins them in lowercase with underscores (my_variable_name). camelCase is the norm in JavaScript and Java, snake_case in Python and SQL.

Copy the kebab-case row. It splits your text into words, drops every punctuation mark, folds accented letters to their plain form, and joins the result with hyphens — so Hola, ¿qué tal? becomes hola-que-tal.

CONSTANT_CASE is the convention for environment variables and fixed constants. dot.case is used for configuration paths, namespaces and feature flags. Train-Case is the shape of HTTP header names such as Content-Type.

Paste the text and copy the lower case row. If the text was shouting and you want readable prose rather than flat lowercase, copy the Sentence case row instead — it restores a capital at the start of each sentence.

Yes. All conversions run locally in your browser, so your text never leaves your device and nothing is sent to a server.