Text Case Converter
Convert text to UPPERCASE, lowercase, Title Case, Sentence case, camelCase, snake_case, kebab-case and more.
Text case converter
What Is a Text Case Converter?
A text case converter changes capitalization and word separators without requiring you to retype text. It can convert ordinary writing into uppercase, lowercase, sentence case, or title case, and it can convert developer naming styles such as camelCase, PascalCase, snake_case, and kebab-case.
How to Use the Text Case Converter
- Type or paste your text, or load a .txt / .md file.
- Choose a case format. Live mode updates the result as you type.
- Review the converted text.
- Copy the result or download a .txt file.
- Use as input to chain another transformation.
- Enable line-by-line processing when converting lists of identifiers.
Common Uses for a Text Case Converter
- Writers: fix headings and capitalization.
- Developers: convert API or database names between naming conventions.
- Marketers: format headlines and campaign text.
- Students: clean copied notes.
- Editors: normalize capitalization before publication.
- Data cleanup: standardize column or label values.
- URL and file naming: generate kebab-case or slug-case.
Convert Text for Code and Data
Developer formats change both capitalization and separators. These are common conventions, not required names for every language.
- user_profile_image_url → userProfileImageUrl (camelCase, acronyms off) or userProfileImageURL (acronyms on)
- user-profile-image → userProfileImage
- User Profile Image → UserProfileImage (PascalCase)
- API response status → apiResponseStatus, or apiResponseSTATUS if acronyms are preserved
camelCase is common for JavaScript variables. PascalCase is common for classes and many React components. snake_case is common for Python and database fields. kebab-case and slug-case are common for URLs and file names. CONSTANT_CASE is common for constants and environment variables.
Title Case vs Sentence Case
| Style | Typical use |
|---|---|
| Title Case | Headlines and titles. First and last words are capitalized; short function words stay lowercase unless they sit at either end. |
| Sentence case | Normal sentences, paragraphs, and many UI labels. The first letter of each sentence is capitalized. |
| Capitalize Each Word | Every word is capitalized. It is not editorial title case. |
Title-case conventions vary by style guide. This tool uses a general title-case rule. It is not an official AP, Chicago, APA, or MLA implementation.
Case comparison
| Case | Example | Common use |
|---|---|---|
| UPPERCASE | HELLO WORLD | Headings, emphasis, constants |
| lowercase | hello world | Normalization |
| Sentence case | Hello world | Paragraphs and many UI labels |
| Title Case | Hello World | Headlines |
| camelCase | helloWorld | JavaScript-style identifiers |
| PascalCase | HelloWorld | Classes and components |
| snake_case | hello_world | Python and database fields |
| kebab-case | hello-world | URLs, CSS, file names |
| CONSTANT_CASE | HELLO_WORLD | Constants and env names |
| dot.case | hello.world | Namespaced keys |
| path/case | hello/world | Path-like identifiers |
| slug-case | hello-world | URL slugs |
How Text Case Conversion Works
- Detect or split tokens.
- Normalize words where the selected format requires it.
- Apply the capitalization rule.
- Rejoin words with the target separator.
- Preserve or transform punctuation according to the mode.
Writing cases mostly change capitalization and keep punctuation. Developer cases change capitalization and separators. Sentence segmentation uses Intl.Segmenter when the browser supports it.
Examples
Input: user_profile_image_url
- camelCase: userProfileImageURL with acronyms on, userProfileImageUrl with acronyms off
- PascalCase: UserProfileImageUrl with acronyms off
- snake_case: user_profile_image_url
- kebab-case: user-profile-image-url
- CONSTANT_CASE: USER_PROFILE_IMAGE_URL
Input: THE QUICK BROWN FOX
- Sentence case: The quick brown fox
- lowercase: the quick brown fox
- Title Case: The Quick Brown Fox
Uppercase, title case, camelCase, and kebab-case
An uppercase converter and a lowercase converter only change letter case. A title case converter and a sentence case converter apply different capitalization rules. A camelCase converter, snake case converter, or kebab case converter also changes separators so identifiers and slugs stay valid.
Common mistakes
- Confusing Title Case with Capitalize Each Word.
- Assuming Title Case follows one universal rule.
- Destroying acronyms such as API or HTML.
- Converting identifiers without checking numbers.
- Converting URLs with the wrong separator. Prefer kebab-case or slug-case when the site uses hyphens.
- Using Title Case for JavaScript variable names. Use camelCase instead.
- Using snake_case in a URL when the convention is hyphens.
- Assuming sentence case fixes grammar.
- Expecting case conversion to fix spelling.
- Ignoring proper nouns after conversion. “paris is beautiful” becomes “Paris is beautiful” only because it starts the sentence.
What this tool does not do
This is a case-conversion tool, not a grammar checker, spell checker, semantic editor, or proper-noun detector. Acronyms and brand names may still need a quick manual review, especially after Title Case or Sentence case. Need to count words after converting? Use the Word Counter. Need to compare two versions? Use the Text Diff Tool. Need structured data? Use the JSON Formatter. Need only whitespace cleanup? Use Remove Extra Spaces.
Frequently asked questions
What is a text case converter?
It changes capitalization and, for developer formats, word separators. You can convert writing styles and identifier names without retyping.
How do I convert text to uppercase?
Paste the text and choose UPPERCASE. Every letter that has an uppercase form is capitalized.
How do I convert text to lowercase?
Choose lowercase. Punctuation and line breaks stay in place unless you enable a cleanup option.
How do I convert text to Title Case?
Choose Title Case. The first and last words are capitalized. Short function words stay lowercase unless they sit at either end. Apostrophes in words such as don't stay intact.
What is the difference between Title Case and Sentence case?
Title Case is for headlines. Sentence case capitalizes the first letter of each sentence and is better for paragraphs and many UI labels.
What is Capitalize Each Word?
It capitalizes every word and ignores editorial small-word rules. That is not the same as Title Case.
How do I convert text to camelCase?
Choose camelCase. Tokens are split on spaces, punctuation, and identifier boundaries, then joined with the first word lowercase.
How do I convert text to PascalCase?
Choose PascalCase. It uses the same tokens as camelCase, but every word starts with a capital letter.
How do I convert text to snake_case?
Choose snake_case. Words are lowercased and joined with underscores. This is common for Python and database fields.
How do I convert text to kebab-case?
Choose kebab-case. Words are lowercased and joined with hyphens. This is common for URLs, CSS names, and files.
What is CONSTANT_CASE?
CONSTANT_CASE is uppercase words joined with underscores. It is commonly used for constants and environment variables.
What is the difference between camelCase and PascalCase?
Both join words without spaces. camelCase starts lowercase (helloWorld). PascalCase starts uppercase (HelloWorld).
What is the difference between snake_case and kebab-case?
snake_case uses underscores. kebab-case uses hyphens. The words are otherwise the same lowercase tokens.
Can the converter preserve line breaks?
Yes. Writing formats keep line breaks by default. Cleanup options can collapse spaces or extra blank lines if you turn them on.
Can I convert multiple lines at once?
Yes. Enable Process each line separately for developer formats to convert lists such as first_name, last_name, and email_address.
Can I upload a text file?
You can load a .txt, .md, or .csv file in the browser. The file is not uploaded for normal conversion.
Is my text uploaded to a server?
No. Text is processed in your browser and is not uploaded during normal conversion.
Does the converter handle acronyms?
When Preserve acronyms is on, known tokens such as API, HTTP, URL, JSON, HTML, and CSS are kept where the format allows. The list is not every proper noun.
Does the converter support Unicode text?
It uses Unicode-aware JavaScript casing, including locale options for English, Turkish, and German. Characters without a case pair are left unchanged.
Can I download the converted text?
Yes. Download a .txt file from the output panel. Prefer copy or download instead of putting private text in a URL.