Case Converter

About the Case Converter

The Case Converter changes the capitalisation of any text in one click. It fixes paragraphs accidentally typed with Caps Lock on, turns rough notes into proper sentences, formats headlines in Title Case, and creates variable, file and CSS names in the programming styles developers use, such as camelCase, snake_case and kebab-case.

Thirteen styles are available, and you can chain them: convert once, click “Use result as input” and apply another. Writers, students, social media managers, data-entry staff and programmers all use it to save the tedious work of retyping. The conversion happens instantly in your browser, so emails, reports and code you paste here are never uploaded.

What are text cases?

“Case” refers to whether letters are written as capitals (uppercase) or small letters (lowercase). The name comes from the printing trade, where metal capital letters were kept in the upper case of type and small letters in the lower case.

In writing, Sentence case capitalises only the first word of each sentence (and proper nouns), and is the normal style for body text and many modern headings. Title Case capitalises the main words of a title but keeps short connecting words such as “of”, “and” and “the” lowercase unless they start or end the title.

In programming, spaces are not allowed in names, so other conventions join words together. camelCase (userFirstName) and PascalCase (UserFirstName) are common in JavaScript, Java and C#. snake_case (user_first_name) is standard in Python and databases. kebab-case (user-first-name) is used in URLs and CSS class names, and CONSTANT_CASE for constants and environment variables.

How to use the Case Converter

1. Type or paste your text into Text to convert, or click Try example.
2. Choose a style from the buttons at the top: Sentence case, lowercase, UPPERCASE, Title Case, Capitalize Each Word, aLtErNaTiNg, iNVERSE, camelCase, PascalCase, snake_case, kebab-case, CONSTANT_CASE or dot.case.
3. Read the result in Converted text; it updates immediately when you change the text or the style.
4. Click Copy result to copy it, or Download to save it as a text file.
5. To apply a second conversion, click Use result as input and choose another style.

Programming styles are applied line by line, so a list of field names, one per line, is converted in a single step.

Key features and benefits

• 13 case styles. Everyday writing styles plus six programming conventions
• Smart Title Case. Keeps 23 common short words (a, an, and, of, the, to, with…) lowercase in the middle of a title
• Sentence case that fixes “i”. Capitalises the start of each sentence and the pronoun “I”
• Programming-aware splitting. Splits words on spaces, punctuation and existing capitals, so userName becomes user_name
• Line-by-line conversion. Convert whole lists of names or column headings at once
• Chaining, copy and download. Reuse the result as input, copy it or save it as a file
• Private. Runs in your browser with no upload

Practical examples

Fixing Caps Lock

Input: PLEASE SEND THE REPORT BY FRIDAY. i WILL CHECK IT. Sentence case gives Please send the report by friday. I will check it. Days, names and places are not recognised automatically, so correct “Friday” by hand.

A blog headline

Input: the history of pakistan and the subcontinent. Title Case gives The History of Pakistan and the Subcontinent: “of”, “and” and “the” stay lowercase in the middle, while the first word is capitalised.

Variable and database names

A list of form fields, one per line: First Name, Date of Birth, Phone Number (Mobile). snake_case gives first_name, date_of_birth and phone_number_mobile; camelCase gives firstName, dateOfBirth and phoneNumberMobile.

CSS classes and constants

Main Navigation Bar in kebab-case is main-navigation-bar, ready for a class name. max upload size in CONSTANT_CASE becomes MAX_UPLOAD_SIZE.

Quick reference: one phrase in every programming style

The phrase user first name converted with each programming option, with where each style is typically used:

Common use cases

• Office workers fix emails and documents typed with Caps Lock on, without retyping.
• Writers and bloggers format headings consistently in Title Case or Sentence case.
• Developers convert field names between camelCase, snake_case and kebab-case when moving between languages, APIs and databases.
• Data-entry staff clean spreadsheet columns of names and addresses.
• Social media managers create stylised alternating or inverse text for informal posts.

Accuracy, limitations and privacy

Conversions use Unicode-aware rules, so accented letters and many non-English alphabets change case correctly. Title Case and Sentence case first convert the text to lowercase and then capitalise the right letters, which means acronyms such as “NASA” or brand names such as “iPhone” are changed and need fixing by hand. Programming styles remove accents (café becomes cafe) and drop punctuation, because most programming languages do not allow them in names.

Scripts without capital letters, such as Urdu and Arabic, are left unchanged. Everything runs in your browser, and nothing is uploaded or stored.

• Proper nouns, acronyms and brand names cannot be detected automatically; check them after converting.
• Title Case follows a common general rule; specific style guides (AP, Chicago, APA) differ on some words.
• Very long texts may take a moment to convert on older phones.

Tips and best practices

• For website headings, pick one style (Title Case or Sentence case) and use it consistently across the site.
• After converting a Caps Lock paragraph, scan it for names, places, days and acronyms.
• Use kebab-case for URLs and file names; for search-friendly URLs the Text to Slug tool also removes stop characters.
• Match the naming convention of the language or framework you are using rather than mixing styles.
• Use aLtErNaTiNg and iNVERSE text sparingly: screen readers and search engines read them poorly.

Related tools and next steps

For one-way fixes, the Uppercase to Lowercase and Lowercase to Uppercase tools are quicker. Turn titles into URL-friendly slugs with Text to Slug, tidy spaces and line breaks with the Text Cleaner, and create bold or italic Unicode text for social media with the Unicode Text Converter. Check the length of your final text with the Word Counter.