How to use the case converter
Paste your text and press a button. The conversion replaces the text in the box, so you can chain them — lower case, then Title Case — and step back with Undo (or Ctrl+Z) at any point. Select part of the text first and only that part changes, which is ideal for fixing one heading in a longer document. Character, word, sentence and line counts under the box update as you go; for the full breakdown with platform limits, use the character counter.
Keep acronyms is on by default. Words written in capitals — NASA, UK NHS, MPs — survive sentence case and Title Case, as do dotted abbreviations such as U.S. and e.g. Words with a capital in the middle are treated as names and left exactly as typed, so JavaScript, YouTube, McDonald’s, PhD, iPhone and eBay come through unchanged, and in titles a lower-case mcdonald’s or o’neill becomes McDonald’s or O’Neill. Ordinals stay as 1st and 21st, and web addresses, e-mail addresses, file names, @mentions and #hashtags are never touched.
If the whole text was typed with Caps Lock on, it is treated as shouting rather than a string of acronyms, but well-known acronyms such as NHS, BBC and PhD are restored. For names the converter can’t know — your company, a product, a football club — open Always write these words as… and list them; they are applied after every Sentence, Title and Capitalised conversion and remembered in this browser.
Title Case rules by style guide
“Title Case” is not one rule. Every style guide capitalises the first and last word and all nouns, verbs, adjectives and adverbs; they disagree about the small words in between.
| Style | Kept lowercase | Example |
|---|---|---|
| Chicago | Articles, and/but/for/or/nor, and all prepositions, whatever their length | A Walk through the Woods without a Map |
| AP | Articles, conjunctions and prepositions of three letters or fewer | A Walk Through the Woods Without a Map |
| APA | Short (three letters or fewer) articles, conjunctions and prepositions; both halves of hyphenated compounds capitalised | A Walk Through the Woods Without a Map |
| MLA | Articles, all prepositions, coordinating conjunctions and the to in infinitives | A Walk through the Woods without a Map |
| AMA | Articles, coordinating conjunctions and prepositions of three letters or fewer | A Walk Through the Woods Without a Map |
| Bluebook and Wikipedia | Articles, conjunctions and prepositions of four letters or fewer | Walking with the Band from Home |
| New York Times | A fixed list: a, and, as, at, but, by, for, if, in, of, on, or, the, to, vs., via | Walking With the Band From Home |
| UK headline | Everything except the first word, acronyms and names (sentence case) | A walk through the woods without a map |
British newspapers, the BBC and GOV.UK write headlines in sentence case, so pick UK headline for them. The word after a colon, dash, question mark or sentence-ending full stop is capitalised as the start of a subtitle — but not after an abbreviation such as U.S., so “The U.S. and the U.K. Agree” keeps its lower-case and. The first part of a hyphenated compound is always capitalised (Up-to-Date, State-of-the-Art). Common phrasal verbs are recognised, so “Set Up Your Account” and “Give Up on Your Dreams” capitalise the particle as the guides require, and like after a pronoun is treated as a verb. Untick keep small words lowercase to capitalise every word. No converter understands grammar perfectly, so give important headlines a final read.
camelCase, snake_case and other programming cases
| Case | Example | Typical use |
|---|---|---|
| camelCase | userAccountId | JavaScript and Java variables and functions |
| PascalCase | UserAccountId | Classes, React components, C# methods |
| snake_case | user_account_id | Python, Ruby, database columns |
| CONSTANT_CASE | USER_ACCOUNT_ID | Constants and environment variables |
| kebab-case | user-account-id | CSS classes, file names, command-line flags |
| dot.case | user.account.id | Config keys, translation keys |
| Train-Case | User-Account-Id | HTTP headers |
The converter first breaks the input into words — at spaces, punctuation, underscores and hyphens, and at the boundaries inside existing camelCase and PascalCase (XMLHttpRequest becomes xml http request) — then joins them in the chosen style, so you can convert freely between them. With one identifier per line ticked, each line of a list becomes its own identifier. Convert accents to plain ASCII turns café into cafe and Straße into strasse, because most languages and systems only accept ASCII in names.
URL slugs and language-specific casing
Slugify produces a web address segment: lower case, ASCII only, words joined by hyphens, with & spelt out as and. Accents are transliterated rather than dropped, and Cyrillic and Greek letters are romanised, so “Crème Brûlée & Café” becomes creme-brulee-and-cafe and “Привет мир” becomes privet-mir. Keep slugs short and descriptive; a slug is part of the page’s address and is hard to change once people link to it.
Upper and lower case are not the same in every language. In Turkish and Azerbaijani, the capital of i is İ and the lower case of I is ı; with the default rules, “istanbul” would wrongly become “ISTANBUL” without the dot. Choose the language under Language rules to get it right. Dutch capitalises the IJ digraph together (IJsselmeer), German ß becomes SS in capitals, and Greek drops accents and uses the final sigma correctly. Reversed or decorative text is a job for the reverse text generator instead.
Frequently asked questions
What is the difference between Title Case and Capitalised Case?
Capitalised Case puts a capital at the start of every single word, including “a”, “of” and “the”. Title Case follows a style guide: it capitalises the important words but keeps short articles, conjunctions and prepositions in lower case unless they are the first or last word, as in “The Lord of the Rings”.
Which Title Case style should I use?
Use whatever your publication follows. US news and PR usually follow AP; books and many websites use Chicago; academic papers use APA, MLA or AMA; legal writing uses Bluebook. British newspapers, the BBC and GOV.UK use sentence-case headlines, which the UK headline option produces. With no house style, Chicago is the most widely recognised. The guides mostly differ over prepositions of four letters or more.
How do I convert only part of my text?
Select the words you want to change in the text box, then press a case button. Only the selection is converted and it stays selected, so you can try another case straight away. Press Undo to reverse the change. Without a selection, the whole text is converted.
Why did “istanbul” become “ISTANBUL” without the dot?
Because standard English casing rules were applied. In Turkish, lower-case i with a dot has the capital İ, and I without a dot has the lower case ı. Select Turkish (or Azerbaijani) under Language rules and upper case gives İSTANBUL, while lower case turns “ISPARTA” into “ısparta” correctly.
Does converting to sentence case keep names and acronyms?
It keeps acronyms such as NASA, UK and MPs, dotted abbreviations such as U.S., and names with an internal capital such as JavaScript, McDonald’s or iPhone. It always capitalises the word I and does not start a new sentence after e.g., Mr. or p.m. It cannot recognise ordinary proper nouns, so London or Sarah become lower case mid-sentence; add names you use often to the ‘Always write these words as’ list.
Why does my web address or e-mail stay in lower case?
Because capitalising it would break it or look wrong. Anything that looks like a web address (example.com, www.bbc.co.uk, a link starting https://), an e-mail address, a file name such as report.pdf, an @mention or a #hashtag is left exactly as you typed it in every writing case. If a word is caught by mistake, convert it by selecting just that word, or add it to your custom word list.