Text Case Converter

What each style does

• Title Case — capitalizes each major word, lowercasing common short words like "and" or "the" unless they start the sentence
• Sentence case — capitalizes only the first letter of each sentence
• aLtErNaTiNg cAsE — alternates upper and lower case letter by letter, often used for sarcastic emphasis online

A worked example

Typing the quick brown fox jumps over the lazy dog gives The Quick Brown Fox Jumps Over the Lazy Dog in Title Case. Over is capitalized because it is not on the small-word list, while the stays lowercase because it is. In Sentence case, the input i met JOHN in paris. he said it was fun! becomes I met john in paris. He said it was fun!

Where to check the result by hand

• Acronyms and brand names are flattened: NASA becomes Nasa and iPhone becomes Iphone in Title Case.
• Sentence case lowercases everything first, so names, places and the pronoun I are lowercase until the start of a sentence. Fix those after converting.
• A hyphenated word is treated as one word, so state-of-the-art becomes State-of-the-art, and a word after a colon is not capitalized the way some style guides require.
• The alternating style counts every character, spaces included, so the pattern depends on where the spaces fall: great idea becomes gReAt iDeA.

Good uses

Rescuing a paragraph typed with Caps Lock on, standardizing a column of names or headings before importing it into a spreadsheet, and preparing headlines for a draft. The five versions are shown together, so you can copy the one you want without retyping. Programmer styles such as camelCase and snake_case are not included.

Edge cases, with real input

Title Case keeps a small word lowercase only when it is not the first word, so of mice and men becomes Of Mice and Men, a tale of two cities becomes A Tale of Two Cities, and what to do in 2024 becomes What to Do in 2024. The check does not look at punctuation, so the small word after a colon stays lowercase: the end of the road: a story becomes The End of the Road: a Story, which some style guides would capitalize. Apostrophes and hyphens are fine, as in don't stop e-mail becoming Don't Stop E-mail, but names with capitals inside are flattened, so mcdonald's becomes Mcdonald's.

Title Case treats only plain letters, digits and the underscore as the start of a word, so a word that begins with an accent is not capitalized: élan vital becomes éLan Vital instead of Élan Vital. Sentence case capitalizes after a full stop, question mark or exclamation mark followed by white space, and a line break counts as white space, so first line. then a new line second line becomes First line. followed by Second line on the next line, and indentation is kept. Alternating case always starts with a lowercase letter and counts spaces, so hello becomes hElLo and Hi there becomes hI ThErE.