Change Text Case

How it works

Paste the text into the left pane and choose the target case; the result appears in the right pane as you type. Lowercase and uppercase rewrite the whole text. Title Case lowercases everything first and then raises the first letter after each space, so an apostrophe or a hyphen does not start a new word: 'best-known author' comes back as 'Best-known Author'. Sentence case also lowercases first, then raises the very first letter and any letter that follows a full stop, question mark, exclamation mark or line break — the quickest way to rescue a paragraph typed with Caps Lock on. The casing rules come from the language of the page you are reading, so the English mapping applies here: i uppercases to I and I lowercases to i, with no surprises in words such as 'index' or 'list'. Accented letters are converted rather than dropped, so é becomes É and comes back as é. The line under the result reports how many words and characters went in, and you can copy the output or save it as a .txt file.

This tool is also known as uppercase to lowercase, lowercase to uppercase, title case converter, sentence case converter, change text case.

What is Title case?

Title case capitalises the first letter of every word and lowercases the rest, so 'books to read this summer' becomes 'Books To Read This Summer'. Headings, slide titles, product names and table-of-contents entries use it. Style guides disagree on the detail: Chicago and AP keep articles, short prepositions and conjunctions lowercase unless they open the title, while an automatic conversion capitalises every word without exception. That gap is why a heading run through any converter deserves one last read — the tool has no dictionary and no house style to consult.

What is Sentence case?

Sentence case is ordinary prose: the opening letter of the sentence is a capital, the rest follows normal spelling. It is the fastest way to make a paragraph readable again after it arrived in BLOCK CAPITALS or with Caps Lock left on. An automatic conversion has to work out where sentences begin, so it lowercases everything first and then raises the letter after each full stop, question mark or exclamation mark. Two consequences follow: proper nouns lose their capitals and must be restored by hand, and an abbreviation ending in a dot is treated as the end of a sentence.

What is the difference between dotted İ and dotless I?

In the Turkish alphabet the dotted and dotless i are separate letters, each with its own pair: lowercase i uppercases to İ (iğne → İĞNE) and lowercase ı uppercases to I (ısı → ISI). English has a single pair, i and I. No one mapping can serve both alphabets, which is why software written without a locale in mind uppercases 'izmir' to 'IZMIR' and lowercases 'ILICA' to 'ilica' — both are misspellings in Turkish, and both are the standard failure of a generic case converter. This page converts with the English rules, so English text is safe: i and I trade places and nothing else moves. For Turkish text, switch to the Turkish version of this page, where all four forms go where they belong.

Why most case converters mangle Turkish text

English has one i and its capital is I. Turkish has two separate letters — dotted i/İ and dotless ı/I — so the two alphabets do not share a single rule. A converter that ignores the difference turns 'istanbul' into 'ISTANBUL' instead of 'İSTANBUL', and lowercases 'IŞIK' to 'işik' instead of 'ışık'. The mistakes sit in the middle of a word, where they are easy to miss.

Here the mapping is taken from the language of the page rather than hard-coded, because one locale cannot be right for both alphabets at once. On this English page the English rules apply, so 'index' uppercases to 'INDEX' and no letter picks up a dot it should not have. The Turkish version of this page applies the Turkish mapping, where all four letters find their proper partner. On either page, letters such as ğ, ş, ç, ö and ü are converted by their own case pairs and never stripped.

Which case belongs where

The right case depends on where the text is going. The wrong one makes the same sentence read as shouting, or as carelessness.

• A paragraph typed with Caps Lock left on → sentence case
• Tags, file names, form fields and code lists → all lowercase
• Report headings and slide titles → Title Case
• Signs, coupon codes and lists of abbreviations → ALL UPPERCASE

What the converter cannot decide for you

Title Case capitalises every word, including 'and', 'of' and 'the'. English style guides keep short articles, conjunctions and prepositions lowercase inside a heading, so a title such as 'The Rise and Fall of the Roman Empire' still needs one manual pass. Deciding which words count as short enough takes a house style, not an algorithm.

Sentence case lowercases everything before it starts, which strips the capitals from proper nouns: 'Paris' comes back as 'paris' unless it happens to open a sentence. It also cannot tell an abbreviation from the end of a sentence, so the word after 'Dr.' or 'e.g.' is capitalised too.

Frequently asked questions

How do I change text from uppercase to lowercase?

Paste the text into the left pane and choose 'all lowercase'. The whole text is rewritten as you type, and you can copy it or download it as a .txt file.

Does Title Case keep words like 'and' and 'of' lowercase?

No — every word is capitalised. If you follow a style guide that keeps short conjunctions and prepositions lowercase inside a heading, fix those words by hand after the conversion.

What exactly does sentence case capitalise?

It lowercases the whole text, then raises the first letter of the text and any letter following a full stop, question mark, exclamation mark or line break. Proper nouns are lost in the first step and abbreviation dots are read as sentence ends.

Does this handle the Turkish dotted and dotless i?

This English page uses English casing rules, so i and I simply swap places and 'index' comes back as 'INDEX'. The Turkish version of the same tool applies the Turkish mapping, where the capital of i is İ and the lowercase of I is ı. The page you are on decides, so use the one that matches your text.

Is my text sent anywhere?

No. The conversion runs inside your browser; what you paste never reaches a server and is gone as soon as you close the tab.