Case Converter Online Free
Convert text to uppercase, lowercase, sentence case, title case, or alternating case instantly. No signup, runs entirely in your browser.
Case Converter
How to Use the Case Converter
- 1Paste or type your text into the box above.
- 2Click the case button you want — UPPER CASE, lower case, Title Case, Sentence case, or aLtErNaTiNg. The text updates instantly.
- 3Click Copy to copy the converted text to your clipboard, ready to paste anywhere.
- 4You can chain conversions — apply one, then apply another on the result without pasting again.
When to Use Each Case Type
Choosing the right case for the context makes a real difference to readability and professionalism. Below is a quick guide to when each type is appropriate.
Case Guide by Context
UPPER CASE
Use for acronyms (NASA, HTTP), legal defined terms, spreadsheet headers, and programming constants (API_KEY, MAX_RETRIES). Avoid for long paragraphs.
lower case
Use for general body text, code identifiers, URLs, CSS class names, and email addresses. Some brand names (adidas, iPad) intentionally use lower case styling.
Title Case
Use for article headings, book titles, film titles, product names, and page navigation labels. Standard in journalism and publishing style guides.
Sentence case
Use for subheadings, email subject lines, button labels, UI copy, and social media posts. Google recommends sentence case for Material Design UI elements.
aLtErNaTiNg CaSe
Use for internet humour and memes only. Conveys sarcasm or mockery in informal digital communication — not appropriate for professional writing.
Mixing Cases
You can apply multiple conversions in sequence — for example, first apply Sentence case to fix capitalisation, then copy. Chain conversions to get the exact result you need.
Frequently Asked Questions
What is Title Case and how does it differ from Sentence case?
Title Case capitalises the first letter of every word — "The Quick Brown Fox". Sentence case capitalises only the first letter of each sentence (after a full stop, exclamation mark, or question mark) and leaves everything else lowercase — "The quick brown fox jumps. It is very agile." Title Case is used for headings, book titles, and article headlines. Sentence case is used for subheadings, email subject lines, and body text.
When should I use UPPER CASE?
UPPER CASE (all-caps) is used for acronyms and initialisms (NASA, HTTP, API), for emphasis in informal writing, for constants in many programming languages (MAX_LENGTH, API_KEY), and in legal documents to signal defined terms. Avoid long all-caps paragraphs — they are harder to read and can come across as shouting in digital communication.
What is aLtErNaTiNg CaSe used for?
Alternating case (also called mock caps or sponge-text) is mostly used in internet humour and memes to convey sarcasm or mockery — it originated from the SpongeBob SquarePants meme format. It has no professional use case, but it is a fun novelty.
Does the converter handle punctuation and numbers?
Yes. Punctuation and numbers are passed through unchanged. Only alphabetic characters are affected by case conversions. For example, "hello, world! 123" in Title Case becomes "Hello, World! 123" — commas, exclamation marks, and digits are untouched.
How does Sentence case handle abbreviations?
The Sentence case converter uses a heuristic: it capitalises the first letter after a full stop, exclamation mark, or question mark. It does not distinguish between abbreviations (Dr., etc.) and true sentence endings. For most body text this works well, but text heavy with abbreviations may require a manual touch-up.
Is my text stored or sent anywhere?
No. The converter runs entirely in your browser using JavaScript. Your text is never sent to a server, never logged, and never stored. Closing the tab discards everything. You can paste confidential documents without any privacy concern.
Can I use this for programming variable names?
The converter handles standard English case transformations (upper, lower, title, sentence, alternating). For programming-specific formats like camelCase, PascalCase, snake_case, or kebab-case, those transformations are not currently supported by this tool — a dedicated dev tool would be more appropriate for those conversions.