Case Converter

This free case converter changes the capitalization of your text in one click, across 15 styles. It does proper Title Case following AP or Chicago rules, plus UPPERCASE, lowercase, Sentence case, and code styles like camelCase and snake_case. Everything runs in your browser and nothing is uploaded.

UPPERCASE

THE LORD OF THE RINGS: THE RETURN OF THE KING

What does this case converter do?

It changes the capitalization of your text across 15 styles, from the everyday UPPERCASE and lowercase to proper Title Case following the AP or Chicago rules, plus every identifier style a developer needs. This free converter from ÆON Toolhub works as you type, keeps your line breaks, and never sends your text anywhere.

Pick a style, read the result, copy it. That is the whole tool.

What is the difference between Title Case and Capitalized Case?

This is the distinction most converters ignore, and it matters if you write headlines.

Capitalized Case capitalizes every single word, including "a", "of" and "the". It is simple and predictable, and it is what most tools call "title case".

Title Case follows an actual style guide: small words stay lowercase unless they are the first word, the last word, or the word right after a colon. That is what editors, journalists and academics mean by the term.

Both are here, named honestly, so you can pick the one you actually want.

AP or Chicago: which should you choose?

They agree on almost everything and disagree about prepositions.

Title	AP	Chicago
gone with the wind	Gone With the Wind	Gone with the Wind
the fox jumps over the dog	...Jumps Over the Dog	...jumps over the Dog

AP lowercases prepositions of three letters or fewer, so longer ones like "With", "Over" and "From" stay capitalized. It is common in journalism, marketing and web copy.

Chicago lowercases prepositions regardless of length. It is common in books and academic writing.

Both capitalize the first and last word no matter what, and both capitalize the word after a colon, so a subtitle starts cleanly.

A fair warning: style guides have genuine edge cases, from phrasal verbs to words that work as both preposition and adverb. No automatic tool resolves all of them, and any tool claiming perfect title case is overselling. Use this as a fast, consistent first pass.

What are the programming styles for?

Identifier styles strip punctuation and rebuild your words as a single token, because that is what a variable or a key has to be.

camelCase for JavaScript variables and functions: userFirstName
PascalCase for classes and React components: UserProfileCard
snake_case for Python and SQL columns: user_first_name
kebab-case for URLs, CSS classes and file names: user-first-name
CONSTANT_CASE for environment variables and constants: MAX_RETRY_COUNT
dot.case for config keys and feature flags: feature.new.checkout
Train-Case for HTTP headers: Content-Type, Accept-Language

The converter also understands existing camelCase and PascalCase boundaries, so you can go from one identifier style straight to another without breaking the words apart by hand.

What about tOGGLE and aLtErNaTiNg?

tOGGLE cASE flips whatever case each letter already has. It is the repair tool for a paragraph typed with Caps Lock on by mistake, where the sentence came out inverted.

aLtErNaTiNg alternates up and down as it goes, regardless of the original. It is used for a sarcastic tone online and, occasionally, to make a label deliberately hard to read.

Does it keep line breaks and punctuation?

Yes for every style that only changes capitalization, including Sentence case, which treats each new line as the start of a sentence. That matters for lists and multi-line text, where a naive converter leaves every line after the first in lowercase.

The identifier styles are the deliberate exception: they collapse everything into one token and drop punctuation, because an identifier cannot contain spaces or commas.

Your text stays private

The converter runs entirely in your browser. What you paste is never uploaded, logged, or stored, and it clears when you close the tab. It also keeps working offline once the page has loaded. If you need to count what you wrote, our word counter is one click away.

Frequently asked questions

What is Title Case and how is it different from Sentence case?

Title Case capitalizes the first letter of every word, the way headlines and titles are written. Sentence case capitalizes only the first letter of each sentence, like normal prose. For example, 'the quick brown fox' becomes 'The Quick Brown Fox' in Title Case and 'The quick brown fox' in Sentence case.

What are camelCase, snake_case, and kebab-case for?

These are naming styles used in programming. camelCase joins words with each new word capitalized, like myVariableName. snake_case joins them with underscores, like my_variable_name. kebab-case uses hyphens, like my-variable-name. Developers pick one to match the language or project style they are working in.

Does converting to a code style remove my punctuation?

Yes, for the programming styles. camelCase, PascalCase, snake_case, kebab-case, and CONSTANT_CASE turn your text into a single identifier, so spaces and punctuation become separators or are removed. The plain styles, like UPPERCASE and Title Case, keep your punctuation and spacing exactly as they were.

Is my text sent to a server?

No. The case converter runs entirely in your browser with JavaScript. The text you paste is never uploaded, logged, or stored, and it disappears when you close or refresh the tab. You can convert private or sensitive text safely, and it works offline once the page has loaded.

How does Title Case handle small words like 'a' and 'the'?

That is exactly what the AP and Chicago options are for: both keep articles, conjunctions and short prepositions lowercase, unless the word is first, last, or follows a colon. If you would rather capitalize every single word, pick Capitalized Case instead, which is the simple rule.

What is the difference between AP and Chicago title case?

They disagree about prepositions. AP lowercases only those of three letters or fewer, so it writes "Gone With the Wind". Chicago lowercases prepositions regardless of length, giving "Gone with the Wind". Both capitalize the first and last word, and both lift the word after a colon.

What is tOGGLE cASE?

It flips the case of every letter: capitals become lowercase and lowercase becomes capitals. It is the fix for text typed with Caps Lock on by accident, where the first letter of each sentence came out small and everything else came out shouting.

What are dot.case and Train-Case for?

Both are identifier styles. dot.case joins lowercase words with periods and shows up in config keys and feature flags, such as feature.new.checkout. Train-Case capitalizes each word and joins with hyphens, which is the shape of HTTP headers like Content-Type and Accept-Language.

Does it keep my line breaks?

Yes, for every style that only changes capitalization, including Sentence case, which now treats each new line as the start of a sentence. The identifier styles like camelCase and snake_case collapse everything into a single token by design, because that is what an identifier is.

Which case should I use for a headline?

Follow whichever guide your publication uses: AP is common in journalism and marketing, Chicago in books and academia. If you have no house style, pick one and stay consistent, because mixed capitalization across headings is far more noticeable to a reader than the choice itself.

Last updated: September 17, 2026