Case conventions carry meaning. Headlines use title case, body text sentence case, constants SHOUT in uppercase and every programming language has rules for when to write firstName, FirstName, first_name or first-name. Retyping a long heading or a column of database fields to match is tedious and error-prone. This converter rewrites text into fourteen styles at once and shows them side by side, so you can copy the one you need.
How to use the case converter
- Paste your text. For code styles you can paste a list — one name per line — and each line converts separately.
- Choose the style in Convert to; it appears large on the tape and in a copyable box.
- Leave Keep acronyms and brand capitals on to protect words like NASA, HTML and iPhone in title and sentence case.
- Scroll to the table to see your text in every style.
The styles
| Style | Example | Typical use |
|---|---|---|
| UPPERCASE | HOW TO READ A MAP | Short labels, emphasis |
| lowercase | how to read a map | Tags, normalizing input |
| Title Case | How to Read a Map | Headlines, titles |
| Sentence case | How to read a map | Body text, UI labels |
| Capitalize Every Word | How To Read A Map | Some product names |
| camelCase | howToReadAMap | JavaScript, Java variables |
| PascalCase | HowToReadAMap | Class and type names |
| snake_case | how_to_read_a_map | Python, database columns |
| CONSTANT_CASE | HOW_TO_READ_A_MAP | Constants, environment variables |
| kebab-case | how-to-read-a-map | URLs, CSS classes, file names |
| Train-Case | How-To-Read-A-Map | HTTP header names |
| dot.case | how.to.read.a.map | Configuration keys |
How the conversion works
Prose styles keep your spacing and punctuation and change only letters. Title case capitalizes every word except a list of short function words, which stay lowercase unless they open or close the title or follow a colon; each part of a hyphenated compound is capitalized (“Long-Term”). Sentence case lowercases everything, then capitalizes the first letter after a period, question mark or exclamation point and the pronoun “I”.
Code styles first split each line into words. A new word starts at any space or punctuation mark and at every change from a lowercase to an uppercase letter, so userId, user_id and “user ID” all split into the same two words. Apostrophes are removed so “don’t” stays one word. The words are then joined with the style’s separator and capitalization.
The converter uses Unicode-aware rules, so accented letters convert correctly (é → É) and German ß uppercases to SS.
Worked example
Input: how to read a NASA press release: the long-term plan for the iPhone era
Title Case: How to Read a NASA Press Release: The Long-Term Plan for the iPhone Era — "to", "a" and "for" stay lowercase, "The" is capitalized after the colon, NASA and iPhone are untouched.
Sentence case: How to read a NASA press release: the long-term plan for the iPhone era.
snake_case: how_to_read_a_nasa_press_release_the_long_term_plan_for_the_i_phone_era — note that the code style splits iPhone at its internal capital.
A list of database columns — first name, lastLoginAt, HTTP status code on three lines — becomes first_name, last_login_at and http_status_code in snake_case, or firstName, lastLoginAt and httpStatusCode in camelCase.
Limits of automatic case
No tool can know every proper noun. Sentence case lowercases every word it cannot recognize as an acronym, so “We flew to Paris” becomes “We flew to paris”; proofread names, places and trademarks afterward. Title case rules also vary between style guides — AP, Chicago and APA differ on prepositions of four or more letters — so check your publication’s guide for edge cases.
To count the words and characters in your text, use the word counter or character counter. To inspect the exact characters (including invisible ones), try the text to ASCII converter.
Frequently asked questions
Which words stay lowercase in title case?
Short articles (a, an, the), coordinating conjunctions (and, but, or, nor, for, so, yet) and short prepositions (at, by, in, of, on, to, up, via, per) stay lowercase unless they are the first or last word or follow a colon. This matches the common core of US style guides; some guides also lowercase longer prepositions such as 'with' or 'from'.
What is the difference between camelCase and PascalCase?
camelCase starts with a lowercase letter (firstName), PascalCase starts with a capital (FirstName). JavaScript and Java use camelCase for variables and functions and PascalCase for classes and types; C# uses PascalCase for most public names.
When should I use snake_case or kebab-case?
snake_case (user_id) is the convention for Python variables and many database columns; CONSTANT_CASE (MAX_SIZE) is used for constants and environment variables. kebab-case (user-id) is common in URLs, file names and CSS class names, where underscores are less readable or not allowed.
Will the converter break acronyms like NASA or brand names like iPhone?
Not in Title or Sentence case while 'Keep acronyms' is ticked: words in all capitals and words with internal capitals are left alone. If the whole text is typed in capitals, the protection switches off automatically so it can be converted. Code styles always normalize letters.