Last updated October 26, 2026
Case Converter
Convert text case
Paste or type text, pick a mode and press Convert. The conversion runs locally in this tab — nothing is sent to a server — and the preview shows the first characters so you can see the shape before copying.
What each mode does
UPPERCASE and lowercase map letters directly. Title Case capitalises every word except short joining words such as of, the and and — the same convention most style guides use for headings. Sentence case lowercases everything and capitalises the first letter only, which is useful for tidying pasted text that arrived in all caps.
Programming cases: camel, snake and kebab
camelCase joins words with no separator and capitalises each word after the first, snake_case joins with underscores and kebab-case joins with hyphens. All three first split the input on spaces, underscores and hyphens, so a sentence, a column header or an existing identifier all convert into the same shape. Lowercase letters are used throughout, which matches how most languages and file names expect identifiers.
Why the alternating mode exists
aLtErNaTiNg cAsE flips case letter by letter. It is a display style for social posts and jokes, not something to use in code or documents. Spaces, digits and punctuation pass through unchanged, so the rhythm stays readable.
When conversion is safe to use
These modes are plain character transforms: they do not fix spelling, add accents or translate. That means acronyms are not preserved in Title Case (NASA becomes Nasa), and hyphenated names may be split. If a document must keep its original capitalisation — legal text, brand names, code identifiers — check the output before pasting it anywhere that matters.
Related text tools
For identifier generation use the UUID generator; for decorative letterforms rather than case changes, the cursive generator maps letters to Unicode alphabets instead of changing their case.
Frequently asked questions
Does the converter send my text anywhere?
No. The conversion runs as JavaScript in this browser tab and the result is written back into the page. Nothing is uploaded, and the tool keeps working after you reload the page offline.
Why does Title Case turn NASA into Nasa?
Title Case here follows the sentence rule — capitalise the first letter of each word and lowercase the rest — with short joining words left lowercase. It has no list of acronyms to check against, so an all-caps acronym is treated as an ordinary word. Fix those by hand if the output is going somewhere formal.
What is the character limit?
5,000 characters per conversion, which covers a long article or a spreadsheet column. Text longer than that is refused rather than truncated, so you never paste a result that silently lost its ending.
Can I convert back?
Yes for case, but not perfectly. Lowercasing then re-capitalising loses the original capitalisation — once letters are flattened, the converter cannot know which words were proper nouns. Keep the source text if you may need to undo the change.