Quick answer: the writing cases are Sentence case (only the first word and names capitalised), Title Case (main words capitalised), UPPERCASE and lowercase. The programming cases join words without spaces: camelCase, PascalCase, snake_case, kebab-case and CONSTANT_CASE.
To switch between them, paste your text into a case converter, or in Word select the text and press Shift + F3.
“Can you change the case?” means something different depending on who’s asking. A writer might mean switching a heading from ALL CAPS to normal sentence case. A developer might mean turning “user name” into userName for a variable. There are really two families of case style — the writing ones, built around grammar and readability, and the programming ones, built around what characters are allowed in code, file names and URLs.
What are the different text case styles?
| Style | Example | Typical use |
|---|---|---|
| Sentence case | Convert your PDF to Word | Headings, interface text, most modern style guides |
| Title Case | Convert Your PDF to Word | Book and film titles, some headline styles |
| UPPERCASE | CONVERT YOUR PDF TO WORD | Short emphasis, acronyms, signs and labels |
| lowercase | convert your pdf to word | Brand styling, casual messages, tidying pasted text |
| camelCase | convertPdfToWord | JavaScript and Java variables and functions |
| PascalCase | ConvertPdfToWord | Class names, React components |
| snake_case | convert_pdf_to_word | Python and Ruby variables, database columns |
| kebab-case | convert-pdf-to-word | URL slugs, CSS class names, file names |
| CONSTANT_CASE | CONVERT_PDF_TO_WORD | Constants and environment variables |
The everyday writing cases
- Sentence case — only the first word and any proper nouns are capitalised, exactly like a normal sentence:
How to share your Wi-Fi with guests. The GOV.UK Design System uses it for all headings, and it’s quicker to read and feels less formal than Title Case. - Title Case — the main words are capitalised:
How to Share Your Wi-Fi with Guests. Traditional for book and film titles and common in American headlines. Which short words stay lowercase (“a”, “the”, “of”, “with”) depends on the style guide — AP, Chicago and APA each draw the line slightly differently — but everyone capitalises the first word. - UPPERCASE — every letter capitalised. Useful for acronyms, short labels and the occasional emphasised word, but long stretches are harder to read and come across as shouting.
- lowercase — no capitals at all. Rare in formal writing, but a deliberate choice for some brands, and a handy first step when cleaning up text that was pasted in capitals.
The programming cases
Names in code usually can’t contain spaces, so these styles use capital letters, underscores or hyphens to keep multi-word names as one unbroken token. Which one you use is mostly decided by the language or project you’re working in.
- camelCase —
firstName,getUserData. The first word stays lowercase and every word after it gets a capital. Standard for variables and functions in JavaScript and Java. - PascalCase —
FirstName,UserProfileCard. Like camelCase but the first word is capitalised too. The usual convention for class names in most languages, and for components in frameworks like React. - snake_case —
first_name,is_available. Words joined with underscores. Standard for variables and functions in Python and Ruby, and very common for database columns and config keys. - kebab-case —
first-name,user-profile-card. Words joined with hyphens. The convention for URL slugs and CSS class names; Google recommends hyphens rather than underscores to separate words in URLs. - CONSTANT_CASE (also called SCREAMING_SNAKE_CASE) —
MAX_RETRIES,API_BASE_URL. Uppercase snake_case, reserved for constants and environment variables so they stand out from ordinary variables.
Two playful extras, aLtErNaTiNg cAsE and iNVERSE cASE (which flips whatever capitalisation was already there), aren’t conventions anywhere — they’re mostly used for sarcastic meme text online.
How to change text case online
- Open Altto’s Case Converter and paste or type your text.
- Pick one of the eleven styles — the result updates instantly as you type or switch.
- Click Copy result. A live word, character and line count sits underneath if you need it (for a fuller count, there’s the Word Counter).
For the programming styles, it first splits your text into words at spaces, hyphens, underscores and lowercase-to-uppercase boundaries, so some-value, someValue and some value all convert the same way. The conversion runs in your browser tab, so nothing you paste is sent anywhere.
Two honest limitations worth knowing. Its Title Case capitalises every word, including short ones like “of” and “the”, and lowercases the rest of each word — so “PDF” becomes “Pdf”. Its Sentence case lowercases everything before capitalising each sentence, so names and acronyms need fixing afterwards. If you’re following a style guide strictly, give the result a quick read-through.
How to change case in Word, Google Docs and Excel
- Microsoft Word: select the text, then use the Change Case button (Aa) on the Home tab, which offers Sentence case, lowercase, UPPERCASE, Capitalize Each Word and tOGGLE cASE. Or press Shift + F3 to cycle between lowercase, UPPERCASE and Capitalize Each Word (on some laptops and Mac keyboards you’ll need to hold Fn as well).
- Google Docs: select the text and choose Format → Text → Capitalization, then lowercase, UPPERCASE or Title Case. There’s no built-in sentence case option.
- Excel and Google Sheets: use the formulas
=UPPER(A1),=LOWER(A1)or=PROPER(A1), the last of which capitalises the first letter of every word. Copy the results and paste them back as values.
None of these do camelCase, snake_case or kebab-case, which is where a dedicated converter earns its place.
Common questions
What’s the difference between Title Case and Sentence case?
What’s the difference between camelCase and PascalCase?
userName) while PascalCase starts with a capital (UserName). In JavaScript and Java, camelCase is used for variables and functions and PascalCase for class names.How do I change text to sentence case in Word?
Why is camelCase used in programming?
firstName or getUserData) uses capital letters instead of spaces to keep multi-word names readable while staying a single unbroken token. It’s the standard convention for variables and functions in JavaScript and Java.What is snake_case used for?
first_name or is_available). It’s the standard naming convention for variables and functions in Python and Ruby, and it’s widely used for database column names and configuration keys, because underscores are safe almost everywhere a space would cause problems.Is typing in ALL CAPS bad for accessibility?
Is my text sent anywhere when I use the Case Converter?
Need to convert some text right now?
Paste it in and switch between 11 case styles, from Sentence case to snake_case — free, no sign-up, and nothing leaves your browser.
Sources
Where the style-guide, Word and URL facts in this guide come from:
- GOV.UK Design System — Headings (headings are written in sentence case)
- Microsoft Support — Change the capitalization or case of text (the Change Case button, and Shift + F3 to cycle through the options)
- Google Search Central — URL structure best practices for Google (use hyphens rather than underscores to separate words in URLs)