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Case Converter

Switch text between UPPERCASE, lowercase, Title Case, Sentence case, and aLtErNaTiNg.

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Quick Answer

Case Converter rewrites your text in any of five cases: UPPERCASE, lowercase, Title Case, Sentence case, and aLtErNaTiNg. Paste your text, click a case, and the converted version appears to copy. Title Case capitalises the first letter of every word, and Sentence case capitalises the start of each sentence. It runs in your browser, and nothing is uploaded.

What the Case Converter Does

Retyping something just to fix its capitalisation is tedious — a heading that came in all caps, a sentence stuck in lowercase, a title that needs each word capitalised. This tool flips text between five cases in one click, leaving your original in place so you can try another.

The five options cover the everyday needs: shout in UPPERCASE, quiet down to lowercase, capitalise every word for a title, fix the start of each sentence, or alternate letters for a playful look.

How It Works

UPPERCASE and lowercase apply the standard letter-case transforms to the whole text. Alternating case walks through the characters, lowering the even positions and raising the odd ones.

Title Case capitalises the first letter of every word and lowercases the rest. Sentence case first lowercases everything, then capitalises the first letter of the text and the first letter after each sentence-ending . ! or ?.

Data source & conversion logic

  1. Step 1. Paste or type your text — it stays in your browser, never uploaded.
  2. Step 2. Click one of the five cases: UPPERCASE, lowercase, Title Case, Sentence case, or aLtErNaTiNg.
  3. Step 3. UPPERCASE and lowercase transform the whole text; alternating toggles letter by letter.
  4. Step 4. Title Case capitalises each word's first letter; Sentence case capitalises after . ! ?.
  5. Step 5. Copy the result; your original text is left untouched.

Technical Details

CasesUPPERCASE, lowercase, Title, Sentence, aLtErNaTiNg
Title CaseCapitalises the first letter of every word
Sentence caseLowercases all, then capitalises sentence starts
CasingBrowser Unicode rules (accented/non-Latin OK)
OriginalKept; result goes to a separate box
UploadNever — runs in your browser

Standards & references

  • Title case — by style-guide rules, title case capitalises major words and lowercases short articles, conjunctions, and prepositions; this tool uses a simpler rule that capitalises the first letter of every word.
  • Sentence case — capitalises only the first word and proper nouns; this tool capitalises sentence starts but, because it lowercases everything first, does not restore proper-noun capitals.
  • Unicode case mapping — upper- and lowercasing follow the browser's built-in Unicode rules, which handle accented and non-Latin letters.

Accuracy & Limitations

UPPERCASE, lowercase, and alternating case are exact transforms — every letter is converted predictably, including accented and non-Latin characters via the browser's Unicode rules.

Title Case here is the simple kind: it capitalises the first letter of every word. Style guides (AP, Chicago, APA) instead lowercase short words like a, of, and, and the — so for a formal, rule-correct title you may need to lowercase those by hand afterwards.

Sentence case lowercases the whole text first, then capitalises the start of each sentence. That fixes shouting or all-lowercase text, but it also strips capitals from proper nouns and the word I (except where one starts a sentence), so names may need fixing.

Sentence boundaries are detected by . ! and ?, so an abbreviation such as Dr. or e.g. can trigger an unwanted capital, and a line with no end punctuation is treated as one sentence.

Real-World Use Cases

Fix all-caps text

Turn a heading or message that arrived in capitals into normal sentence or title case.

Make a quick title

Capitalise each word of a heading or filename in one click.

Normalise pasted text

Bring inconsistent capitalisation into a single, tidy case.

Playful styling

Use alternating case for a meme-style or sarcastic look.

When to use it — and when not to

Good for

  • Switching between the five common cases
  • Fixing all-caps or all-lowercase text
  • Quick title or sentence capitalisation
  • Accented and non-Latin letters

Not the best choice for

  • Strict style-guide title case (minor words stay capitalised)
  • Preserving proper nouns through sentence case
  • Camel, snake, or kebab programming cases
  • Language-specific casing edge cases

For a rule-correct title, a dedicated title-case converter applies style-guide rules; for code identifiers, use a case tool built for camelCase or snake_case.

Frequently Asked Questions

What cases can it convert to?
Five: UPPERCASE, lowercase, Title Case (first letter of every word), Sentence case (start of each sentence), and aLtErNaTiNg case. Click a button to apply one.
Does Title Case follow style-guide rules?
Not strictly. It capitalises the first letter of every word, whereas AP, Chicago, and APA title case lowercase short articles, conjunctions, and prepositions like a, and, and of. You would lowercase those by hand for a formal title.
Why did Sentence case lowercase a name?
Sentence case lowercases the whole text first, then capitalises sentence starts. It cannot tell a proper noun from an ordinary word, so names and the word I lose their capitals unless they begin a sentence. Re-capitalise those manually.
How does it decide where a sentence ends?
By looking for a full stop, question mark, or exclamation mark. That works for normal prose but can miscount around abbreviations and decimals.
Does it change my original text?
No. It writes the converted version to a separate box for you to copy; your input stays as you pasted it, so you can try another case.
Does it handle accented or non-English letters?
Yes. Upper- and lowercasing use the browser's Unicode rules, so accented Latin and many non-Latin scripts convert correctly.
What is alternating case for?
It lowercases and uppercases letters in turn, giving the aLtErNaTiNg look often used for sarcasm or memes. It is purely stylistic.
Can it do camelCase or snake_case?
No — those are programming naming styles, not letter cases. This tool covers the five reading cases; a developer naming-case tool handles camelCase and snake_case.
Is my text uploaded?
No. The conversion happens in your browser. Nothing is sent to a server, and clearing the box removes it.
Can I convert a whole document?
Yes — paste as much text as you like. It converts in your browser, so very large pastes depend on your device, but normal documents are instant.

References

Describes the five modes the tool runs — and is honest that its Title Case capitalises every word and its Sentence case drops proper-noun capitals.

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