The four styles
UPPERCASE and lowercase convert every letter the same way. Title Case capitalizes the first letter of each word; Sentence case capitalizes only the first letter of each sentence and lowercases the rest. Casing follows your browser's locale rules rather than assuming English always applies, which matters for a small number of languages with special casing rules, such as Turkish.
Worked example
The phrase "the quick brown fox jumps over the lazy dog" becomes:
- UPPERCASE: THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG
- Title Case: The Quick Brown Fox Jumps Over the Lazy Dog
- Sentence case: The quick brown fox jumps over the lazy dog
How Title Case handles small words
Capitalizing every single word can look heavy-handed in a title, so this tool follows a common editorial convention: short connecting words such as "a", "the", "of" and "in" stay lowercase in the middle of a title, but are capitalized if they happen to be the first or last word. For example, "the lord of the rings" becomes "The Lord of the Rings".
What it does not do
The converter does not recognize acronyms or proper nouns, so "NASA" in Title Case becomes "Nasa" rather than staying in capitals. Sentence detection uses the same best-effort heuristic as Character Counter, so unusual punctuation or abbreviations can occasionally throw off where one sentence ends and the next begins.