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Quick answer: A case converter changes the letter case of text you paste, from capital letters to small letters or back. This free one has five modes: tOGGLE cASE, Sentence case, lower case, UPPER CASE and Capitalize Word. Paste your text in the box above, pick a case and press Generate.
No sign-up is needed: this online case converter takes 50 words per press, or 100 with a free account. Title case isn't one of the five.
How to Change the Case of Your Text
Watch the preselected tile. A fresh page opens on tOGGLE cASE, which swaps every letter.
Paste text. Click the top box ("Write some text here ...") and paste up to 50 words.
Pick a case. Click a tile, then check it is the one selected.
Press the Generate button. Clicking a tile converts nothing; the page reloads with the result in the second box.
Copy or save. Copy to Clipboard and Save as TXT, which downloads case-converter.txt, appear with the result. Use either before you leave the page.
Try another case. Pick another tile and press Generate again; your original text stays in the top box.
Inside your text, every mode leaves spacing, punctuation and digits alone, and only letters change.
Mode
What it does
Example
Good for
tOGGLE cASE
Swaps capitals to small letters and the reverse.
"hELLO wORLD, tHIS WAS tYPED wITH cAPS lOCK" becomes "Hello World, This was Typed With Caps Lock"
Caps Lock slips
Sentence case
Lowercases all, then capitalizes the first letter of the text, of every line and after each period, question mark or exclamation mark followed by a space, abbreviations such as etc. included.
"THIS WAS TYPED WITH CAPS LOCK ON. SO WAS THIS." becomes "This was typed with caps lock on. So was this."
Sentences and lines
lower case
Turns every capital letter into a small letter.
"The Quick BROWN fox JuMpS" becomes "the quick brown fox jumps"
Calming shouted text
UPPER CASE
Turns every letter into a capital.
The same line becomes "THE QUICK BROWN FOX JUMPS"
Labels and warnings
Capitalize Word
Lowercases all, then capitalizes every word.
The same line becomes "The Quick Brown Fox Jumps"
Headline drafts
The code is plain PHP (mb_strtolower, mb_strtoupper, mb_convert_case, a short loop and two short regular expressions) with no idea what a proper noun is, so the three modes that lowercase first flatten SEO into seo or Seo. Convert only the phrase that needs it.
Capitalize Word vs Title Case: What to Fix by Hand
Capitalize Word is not title case. It capitalizes small words too, so "the lord of the rings: a tale of war" becomes "The Lord Of The Rings: A Tale Of War", and "Of" gets a capital it never earned.
The APA title case rules are pickier: articles, short conjunctions and short prepositions (three letters or fewer) stay lowercase, and every other word gets a capital. Other style guides differ, so check yours. We have no small-word list, so that cleanup is yours.
Capitalize Word breaks words only at a space, tab or line break, so well-known becomes Well-known and O'Neil becomes O'neil. A word that starts with a symbol, such as a bracket, quote mark, # or @, still gets a capital on the first letter after the symbol, so (bracket becomes (Bracket.
Workflow: Run Capitalize Word, lowercase the articles, conjunctions and short prepositions with find and replace (match case on), then fix proper nouns and acronyms. For a page title, see how to write a meta title.
Accents, Acronyms and Other Edge Cases We Tested
We ran these inputs through all five modes in October 2026. The tool uses Unicode-aware case functions, so accented letters, Greek and Cyrillic convert like A to Z, and the results follow the default Unicode mapping.
Your text contains
What happens
What to do
Acronyms and brand names (NASA, iPhone, eBay)
Lower case gives "nasa" and Capitalize Word gives "Nasa". UPPER CASE keeps NASA but turns iPhone into IPHONE.
Retype them, or use UPPER CASE on a true acronym.
Accented letters (diacritics) and the German sharp s
UPPER CASE turns café into "CAFÉ", and lower case turns ÉCOLE into "école". The German ß becomes SS in UPPER CASE and stays as typed inside a word in the other modes.
Check any ß, since UPPER CASE writes it as SS.
Greek, Cyrillic or the Turkish dotless i (αβγ, привет, ışık)
Greek and Cyrillic convert like Latin letters: привет becomes "ПРИВЕТ" in UPPER CASE. Turkish gets the default Unicode mapping, not the Turkish one: istanbul becomes "ISTANBUL" in UPPER CASE, where Turkish writes "İSTANBUL".
Fix a Turkish i by hand. After tOGGLE cASE, a Greek word that ends in σ needs ς instead.
Text starting with a quote, bracket or digit
Sentence case skips a leading quote or bracket and capitalizes the first letter after it. A line that starts with a digit, a space or a dash and a space gets no capital, though the letter after a numbered start such as 1. does.
Capitalize it by hand.
Symbols, emoji, CJK and HTML tags
Symbols, emoji and CJK pass through. Tags show as plain text, and their A to Z letters convert.
Nothing to fix.
Real case mapping is not a letter swap: ß capitalizes to SS, and in Turkish a dotted i capitalizes to İ, as the Unicode case mapping FAQ explains. This tool follows the default mapping, so it writes the SS but not the Turkish İ. Check the result if your text is Turkish.
Limits to Know Before You Paste
A form post and a short PHP script: the edges are easy to list.
Words per press. 50, or 100 with a free account, counted by whitespace, so well-known is one word.
Over the limit. The box is emptied and the tile resets to tOGGLE cASE. There's no word counter, so count first.
One mode per press. There's no live preview, no undo and no file upload.
No code cases. There's no camelCase, snake_case or alternating case.
Where Your Text Goes
This free case converter runs on our server, not in your browser: your text travels to us when you press Generate, so nothing converts while you type. No account is needed.
Keep secrets out: no passwords, ID numbers or anything you wouldn't send to a website.
Which Case to Use and When
Start from how the text looks.
Shouted. An all caps email subject line wants lower case, or Sentence case for an opening capital.
Inverted. Text like hELLO wORLD wants tOGGLE cASE.
A label or an acronym. Only UPPER CASE leaves NASA capital.
Plain names or a headline draft. Capitalize Word, then recheck O'Brien style names and small words.
Frequently Asked Questions (FAQs) is a list of common questions and answers provided to quickly address common concerns or inquiries.
How do I change text from uppercase to lowercase?
To convert to lowercase, paste your text into the top box, pick lower case, press Generate and copy the result from the second box. To convert to uppercase, pick UPPER CASE instead. Sentence case lowercases too but gives the first letter of each sentence a capital.
What is the difference between sentence case and title case?
Sentence case capitalizes the first word and proper nouns, while title case capitalizes a heading's main words. Our Sentence case tile capitalizes the first letter of each sentence and line but no proper nouns, and Capitalize Word every word. APA Style lowercases articles, short conjunctions and short prepositions, so finish by hand.
Does the case converter work with accented letters and other alphabets?
Yes. Accented letters, Greek and Cyrillic convert in every mode, so ÉCOLE becomes école in lower case and café becomes CAFÉ in UPPER CASE. The German sharp s becomes SS in UPPER CASE and stays as typed inside a word in the other modes. Turkish gets the default Unicode mapping, so check Turkish text by hand.
Is there a word limit?
Yes. You can convert 50 words per press without an account, or 100 with a free account, and a line break counts like a space. Over the limit you get an error message and an empty box, and the paste is lost.
Where does my text go when I use this case converter?
Your text goes to our server. The conversion runs there, not in your browser, so it travels to us when you press Generate. Keep passwords, ID numbers and other secrets out of the box. That round trip is why nothing converts as you type.
Is there a case converter in Microsoft Word?
Word has one: Home, then Change case, lists Capitalize Each Word, tOGGLE cASE, Sentence case, lowercase and UPPERCASE. Shift+F3 cycles lowercase, UPPERCASE and Capitalize Each Word. This page helps outside Microsoft Word.
Does it keep my line breaks and spacing?
Yes. Spaces, tabs and line breaks stay exactly as typed, so three spaces stay three, though blank space at either end is trimmed first. Capitalize Word gives every line a capital, and Sentence case does too when a line starts with a letter.
Can I copy or download the converted text, and does it work on a phone?
Yes to both. Copy to Clipboard and Save as TXT appear after you press Generate, and the download is a plain text file, case-converter.txt. Both worked at phone width in our tests, where the page stacks the top box, then the tiles and Generate, then the result box, so scroll down.
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