Case Converter
Convert your text to UPPERCASE, lowercase, Title Case, Sentence case, or aLtErNaTiNg CaSe in one click. The detected case of your input is shown automatically.
How to use the case converter
Paste your text into the editor and click any case button. The converted text appears in the output box instantly. Use Copy to grab it for use elsewhere, or Replace to swap it directly into the editor (Undo is available after Replace). A detected-case badge shows what case your input uses, so you know what you're starting with.
How each case conversion works
UPPERCASE converts every letter to its capital form. lowercase converts every letter to its small form. Title Case capitalises the first letter of content words and lowercases function words (a, an, the, and, but, or, in, on, at, etc.). Sentence case capitalises the first letter after each sentence-ending punctuation mark and lowercases everything else. aLtErNaTiNg CaSe alternates lower and upper on every character.
When you need case conversion
Copying text from PDFs, emails, or legacy systems often introduces inconsistent capitalisation. Heading styles change between style guides (AP, Chicago, APA each have different title case rules). A developer might paste ALL-CAPS constants into a document that expects sentence case. This tool handles all of these situations in under a second.
Frequently asked questions
What is title case?
Title case capitalises the first letter of most words. The exact rules vary by style guide. This tool follows a common rule: capitalise all words except short prepositions (in, on, at, by, for, with), coordinating conjunctions (and, but, or, nor, so, yet), and articles (a, an, the) — unless they are the first or last word of the title. The Chicago Manual of Style and AP Stylebook have slightly different rules; for SEO page titles and blog post headings, this implementation is appropriate.
What is sentence case?
Sentence case capitalises only the first letter of the first word and any proper nouns. It's how you'd write a normal sentence. Most modern web UIs (Google, Apple, Notion) prefer sentence case for headings and UI labels over title case, which is considered more formal. Sentence case in this tool capitalises after every full stop, question mark, and exclamation mark.
What is alternating case used for?
Alternating case (aLtErNaTiNg) has no practical professional use — it originated in mocking or sarcastic internet memes ('the SpongeBob mocking meme'). It's included because people search for it, it's occasionally useful in creative/design contexts, and it takes no effort to add.
How do I convert a whole document to lowercase?
Paste the full text into the textarea, click 'lowercase', then click 'Replace'. This overwrites the input with the converted text. If you change your mind, click 'Undo' immediately — this restores the original text. You can then copy the result or continue editing.
Does title case work for non-English text?
Partially. The capitalisation logic works for any Latin-alphabet language. However, the list of words that should NOT be capitalised (articles, prepositions, conjunctions) is tuned for English. For French, German, Spanish, or other languages, the 'do not capitalise' list is different — the output will over-capitalise minor words in those languages. For English, it's accurate.
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