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Case converter

Paste text and switch it to UPPERCASE, lowercase, Title Case following a style guide, Sentence case, or the camelCase, snake_case and kebab-case styles used in code, then copy the result.

Off: your text is gone when you close the page. It is never sent anywhere.

Change to
For code and file names
Style guide

AP: articles, and conjunctions and prepositions of three letters or fewer (a, and, for, in, of, to…), stay lowercase; longer ones such as With and From are capitalized.

Leaves words typed in capitals, and names like iPhone, as they are. Text typed all in capitals is converted in full.

"Use as my text" replaces your text with the result, so you can convert it again. The link keeps the case and style you chose, never your text.

Words like "up" or "over" can be a preposition or part of a verb ("Give Up"): check those, and names, by eye.

  • Your text stays on your device
  • Free, no sign-up
  • Works on phone and desktop

How to change text case

  1. 1

    Type or paste your text in the box.

  2. 2

    Choose a case: UPPERCASE, lowercase, Title Case, Sentence case or one of the code styles.

  3. 3

    For title case, pick the style guide you follow: AP, APA, Chicago or MLA.

  4. 4

    Copy the result, or use it as your text to convert it again.

Features

  • Title case by style guide

    AP, APA, Chicago and MLA each treat short words differently. Pick yours and the small words follow its rules.

  • Keeps acronyms

    NASA, FBI and names like iPhone stay as you typed them, unless you switch that off.

  • Live as you type

    The result updates with every keystroke, line by line, so a list of headings converts in one go.

  • Private

    Your text is converted in your browser and never sent anywhere. Saving it in this browser is up to you.

Title case rules by style guide

All four major American style guides capitalize the first word of a title and its main words, and keep the articles a, an and the in lowercase inside it. They part ways over short conjunctions, prepositions and the last word:

RuleAPAPA (7th ed.)Chicago (18th ed.)MLA (9th ed.)
PrepositionsLowercase if 3 letters or fewerLowercase if 3 letters or fewerLowercase if 4 letters or fewerAlways lowercase
and, but, or, nor, forLowercaseLowercaseLowercaseLowercase
so, yetLowercaseLowercaseCapitalizedLowercase
to, asLowercaseLowercaseAlways lowercaseLowercase
Last wordAlways capitalizedFollows the rules aboveAlways capitalizedAlways capitalized
After a colonCapitalizedCapitalized (also after an em dash)CapitalizedCapitalized

Chicago's 18th edition, published in 2024, changed its rule: it used to lowercase every preposition, and now capitalizes those of five letters or more, such as About, Through and Between. Here is how the converter handles some titles in each style:

TypedAPAPAChicagoMLA
a tale of two citiesA Tale of Two CitiesA Tale of Two CitiesA Tale of Two CitiesA Tale of Two Cities
a room with a viewA Room With a ViewA Room With a ViewA Room with a ViewA Room with a View
what dreams are made ofWhat Dreams Are Made OfWhat Dreams Are Made ofWhat Dreams Are Made OfWhat Dreams Are Made Of
the man who walked through the wallThe Man Who Walked Through the WallThe Man Who Walked Through the WallThe Man Who Walked Through the WallThe Man Who Walked through the Wall
self-report measures of well-being: a reviewSelf-Report Measures of Well-Being: A ReviewSelf-Report Measures of Well-Being: A ReviewSelf-Report Measures of Well-Being: A ReviewSelf-Report Measures of Well-Being: A Review

In hyphenated words, the first part is always capitalized and later parts are too unless they are short minor words, so "well-being" becomes Well-Being and "up-to-date" becomes Up-to-Date. A word list can't see grammar: "up" in "Give Up" is part of a verb and most guides would capitalize it, while the converter treats it as a preposition. AP also capitalizes the "to" in front of a verb ("How To Write"), which the converter can't tell from "to" meaning direction. Glance over short words like these before you publish.

When to use sentence case

Sentence case capitalizes the first word of each sentence, the word "I" and names, and nothing else. Many websites, apps and company writing guides use it for headings and buttons: it reads like ordinary text and avoids debates about small words. APA uses it for the titles of articles and books in a reference list. It is also the quickest fix for text that was typed with Caps Lock on: "HOW TO WRITE A COVER LETTER. TIPS FROM I.T. RECRUITERS" becomes "How to write a cover letter. Tips from I.T. recruiters".

The converter capitalizes after a full stop, question mark or exclamation mark and at the start of each line, keeps days of the week and most months capitalized, and doesn't start a new sentence after abbreviations such as e.g. and i.e. It can't know which other words are names, so check people and places after converting.

Code cases explained

Programming languages and web addresses don't allow spaces in names, so several words are joined in one of a few standard ways. The converter splits your text into words, including names already written in another case (so XMLHttpRequest becomes xml, http and request), drops punctuation and accents, and joins the words again:

Style"Total amount due"Typical use
camelCasetotalAmountDueVariables and functions in JavaScript, Java and Swift
PascalCaseTotalAmountDueClass and type names; components in React
snake_casetotal_amount_dueVariables in Python and Ruby; database columns
CONSTANT_CASETOTAL_AMOUNT_DUEConstants and environment variables
kebab-casetotal-amount-dueWeb addresses, CSS class names and file names
dot.casetotal.amount.dueSettings keys and some file and package names

Each line is converted on its own, so you can paste a whole list of field names at once. Casing follows English rules: a lowercase i becomes I. In Turkish and Azerbaijani, i pairs with the dotted capital İ and the dotless ı with I, so text in those languages may need a quick fix by hand.

To count what you have written, use the word counter or the character counter for posts and titles with a limit. The alphabetical order tool sorts a list, and the font generator turns text into bold, script and other Unicode styles.

Frequently asked questions

What is title case?

Title case capitalizes the main words of a title (nouns, verbs, adjectives, adverbs and pronouns) and keeps some short words such as "a", "and" and "of" in lowercase, unless they come first. Which short words stay lowercase depends on the style guide, which is why the converter asks for one.

Which words should not be capitalized in a title?

In every major guide: the articles a, an and the, and short conjunctions such as and, but and or, when they fall inside the title. Prepositions are where guides differ: AP and APA lowercase those of three letters or fewer (in, of, on), Chicago those of four letters or fewer (with, from, into), and MLA every preposition, however long (through, between).

Is "with" capitalized in a title?

It depends on the guide. AP and APA capitalize words of four or more letters, so "A Room With a View". Chicago lowercases prepositions of four letters or fewer, and MLA lowercases all prepositions, so both give "A Room with a View".

What is the difference between title case and sentence case?

Sentence case capitalizes only the first word and names, as in an ordinary sentence: "The road not taken". Title case capitalizes the main words: "The Road Not Taken". Sentence case is common for headings on websites and in apps, and APA uses it for the titles of articles and books in reference lists.

Will it change names and acronyms?

With "Keep acronyms" on, words typed in capitals (NASA, UK) and names with capitals inside (iPhone, McDonald) are left alone. Ordinary names such as Paris or Maria can't be told apart from other words, so sentence case lowercases them; check them after converting. In text typed all in capitals, acronyms can't be picked out, so they are converted too, except dotted ones such as U.S.

What are camelCase and snake_case?

Ways of writing several words as one name, without spaces, for code and files. camelCase starts each word after the first with a capital (totalAmountDue), snake_case joins lowercase words with underscores (total_amount_due), and kebab-case uses hyphens (total-amount-due), which suits web addresses.

Is my text saved or uploaded?

It is never uploaded. By default it disappears when you close the page. If you turn on "Keep my text in this browser", it is stored on your own device so it is still there next time; turning it off deletes it.

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