Text Case Converter
Convert text to UPPERCASE, lowercase, Sentence case, Title Case (AP, Chicago, APA or MLA rules), camelCase, PascalCase, snake_case, CONSTANT_CASE, kebab-case and more — line by line, with word, character, sentence and line counts.
How it works
UPPERCASE / lowercase = change every letter · Sentence case = lowercase, then capitalize after . ! ? and at each line start · Title Case = capitalize every word except short "minor" words (articles, coordinating conjunctions, short prepositions — the style guide sets which), always capitalizing the first word, the first after a colon and, in AP, Chicago and MLA, the last · Code styles = split into words, then join: camelCase / PascalCase (no separator), snake_case / CONSTANT_CASE (_), kebab-case / Train-Case (-), dot.case (.)
The converter produces fifteen versions of your text at once and highlights the one you pick. Letter-case styles keep your words and punctuation and change only capitalization: UPPERCASE and lowercase map every letter (accented letters and ñ included), Sentence case capitalizes the start of each sentence and line (and the pronoun “I”), Capitalize Each Word gives every word a capital, and alternating and inverse case are novelty styles. Title Case follows a real style guide. All of them lowercase the articles a, an and the and capitalize the first word, the first word after a colon or dash, nouns, verbs, adjectives and adverbs; they differ on the small words. AP and APA lowercase conjunctions and prepositions of three letters or fewer (so “Into” and “Over” are capitalized), Chicago lowercases prepositions of up to four letters plus and, but, for, or and nor, and MLA lowercases every preposition whatever its length. AP, Chicago and MLA also capitalize the last word; APA does not. A second table compares the styles side by side, and the steps explain each word’s decision. Acronyms and words with inner capitals (NASA, iPhone) are kept unless the whole text is in capitals. The code styles first split the text into words — at spaces, punctuation and existing camelCase humps — then rejoin them, one name per line, so a pasted list of column names converts in one go. Counts of words, characters, sentences and lines are shown alongside.
Worked example
“wildlife photography through every season / a quick guide to shooting birds over water” in AP style becomes “Wildlife Photography Through Every Season / A Quick Guide to Shooting Birds Over Water”. Chicago lowercases the four-letter preposition: “…Shooting Birds over Water”, and MLA also lowercases “through”: “Wildlife Photography through Every Season”. “to” and the article “a” stay lowercase except where “A” starts the second line. As code, the first line becomes wildlifePhotographyThroughEverySeason (camelCase), wildlife_photography_through_every_season (snake_case) and WILDLIFE_PHOTOGRAPHY_THROUGH_EVERY_SEASON (CONSTANT_CASE). The text has 13 words, 84 characters and 2 lines.
Sources: The Chicago Manual of Style, 18th ed. (2024), 8.160 Headline-style capitalization · APA Style: Title case capitalization · MLA Style Center: Titles · RAE: Mayúsculas en títulos (Ortografía de la lengua española)
Frequently asked questions
What is the difference between Title Case and Sentence case?
Title Case capitalizes the main words of a heading and leaves short words such as articles and prepositions lowercase (“A Guide to the Night Sky”). Sentence case capitalizes only the first word of each sentence and proper names (“A guide to the night sky”), the style used for body text, most interface labels and Spanish titles.
Which title case style should I use — AP, Chicago, APA or MLA?
Use AP for news and blog headlines, Chicago for books and many magazines, APA for academic papers in psychology, education and the social sciences, and MLA for papers in literature and the humanities. If you have no house style, AP or Chicago are the usual choices; the comparison table shows how your title looks in each.
Why is “with” capitalized in AP but not in Chicago?
AP and APA capitalize every word of four letters or more, so With, From, Into and Over get a capital. Chicago (18th edition) lowercases prepositions of up to four letters, and MLA lowercases prepositions of any length, so they write “with”, “from” and even “through” in lowercase.
Can it tell when “up” or “over” is not a preposition?
No converter can be sure, because the same word can be a preposition (“Over the Wall”) or part of a verb or adjective (“Game Over”, “Give Up”). This tool lowercases common prepositions and capitalizes up, out, off and down, which are usually verb particles. The steps list every decision so you can fix the rare exception.
When would I use camelCase, snake_case or kebab-case?
They are naming conventions in code and data. camelCase (myVariableName) is common for JavaScript and Java variables, PascalCase (MyClassName) for classes and components, snake_case for Python and database columns, CONSTANT_CASE for constants and environment variables, and kebab-case for URLs, CSS classes and file names. Paste a list with one name per line to convert them all at once.
Does it handle accents, ñ and other languages?
Yes. Capitals and small letters are changed with full Unicode rules, so á, é, ñ, ü and ç keep their accents (niño → NIÑO), and Sentence case skips the opening ¿ and ¡ of Spanish questions. Code styles keep accented letters by default; turn on “Remove accents” to get plain ASCII names such as nino instead of niño.
How are words, sentences and lines counted?
A word is a run of letters or digits, with inner apostrophes and hyphens included (don’t and well-known count as one word). A sentence ends at a period, exclamation mark or question mark followed by a space or the end of the text. Lines are the non-blank lines of your text. Characters count every character including spaces.
Related calculators
This calculator is for educational purposes. Double-check important results before acting on them.