Case Converter

About text case

Text case controls how letters are capitalized. UPPERCASE makes every letter capital; lowercase makes every letter small. Title Case capitalizes the first letter of each word, useful for headings. Sentence case capitalizes only the first letter of the whole text, as in a normal sentence.

How do I convert text between UPPERCASE, lowercase, Title Case, and Sentence case?

To convert case, apply a rule to every letter based on its position: UPPERCASE and lowercase change every letter uniformly, Title Case capitalizes the first letter of each word, and Sentence case capitalizes only the first letter of the whole text. Example: "hello WORLD from EARTH" becomes "Hello World From Earth" in Title Case and "Hello world from earth" in Sentence case.

Steps to convert text case

1. For UPPERCASE, convert every letter in the text to its capital form, leaving numbers and symbols unchanged.
2. For lowercase, convert every letter to its small form the same way.
3. For Title Case, split the text into words on whitespace, then for each word capitalize the first letter and lowercase the rest.
4. For Sentence case, first lowercase the entire text, then capitalize only the very first letter of the result.
5. Copy the converted output with the Copy button; the original input text is left untouched in the input box so you can try another case style.

Case conversion rules

• Word = a run of non-whitespace characters, as split by spaces, tabs, or line breaks
• Title Case capitalizes every word independently; Sentence case capitalizes only the first character of the entire text

camelCase and snake_case, explained

What is camelCase?

camelCase joins words with no spaces, lowercases the first word, and capitalizes the first letter of each following word, like helloWorld. This tool does not output camelCase; it converts between UPPERCASE, lowercase, Title Case, and Sentence case.

What is snake_case?

snake_case joins words with underscores and keeps every letter lowercase, like hello_world. This tool does not output snake_case; it converts between UPPERCASE, lowercase, Title Case, and Sentence case.

What is the difference between Title Case and camelCase?

Title Case keeps spaces between words and capitalizes each word's first letter (Hello World), while camelCase removes the spaces entirely and only capitalizes the first letter of words after the first (helloWorld). This tool produces Title Case, not camelCase.

Example conversions

Frequently asked questions

Why does Title Case capitalize small words like "the" and "of" too?

This tool applies a simple rule that capitalizes the first letter of every word without exception, which is easier to predict and verify than style-guide rules that keep certain short words (a, the, of, and) lowercase unless they start the sentence. If you need style-guide-accurate title casing, review the output for those specific words.

What happens to numbers and punctuation during conversion?

Numbers, punctuation, and symbols have no uppercase or lowercase form, so all four conversions leave them completely unchanged; only alphabetic characters are affected. A word like "COVID-19" keeps its hyphen and digits in every case style.

How is Sentence case different from just capitalizing the first letter I already typed?

Sentence case first lowercases the entire text before capitalizing the first letter, so it also fixes any unwanted capitals later in the text (like "Hello WORLD" becoming "Hello world"). Simply capitalizing the first letter of the original text would leave mid-text capitals untouched.

Does converting case affect accented or non-Latin letters?

Yes, this tool uses the browser's built-in toUpperCase() and toLowerCase() methods, which correctly handle accented Latin letters (é, ñ, ü) and many other scripts that have case distinctions, following standard Unicode case-mapping rules.

This tool performs simple rule-based case conversion using JavaScript's built-in string methods; it does not apply style-guide-specific title-casing exceptions (keeping short words like "a" or "of" lowercase) and does not detect proper nouns or acronyms that might need special capitalization.

Privacy and safety

• Runs in your browser — Everything you type is calculated on your own device. Your inputs are never sent to a utilduck server.
• Encrypted connection — Pages are served over HTTPS, so nobody on the network can read what you load.
• Not shared with third parties — Your inputs are not passed to analytics or advertising services.
• Nothing is stored — Results are not saved to any server, and there is no account to create.

Last updated: 2026-08-17