How to use this case converter
- Paste your text into the box above, or type it directly.
- Pick a case style. The result updates immediately in the box below.
- Try a different style if the first one is not quite right. Nothing is lost.
- Press Copy result to put the converted text on your clipboard.
- Or download it as a plain text file if you would rather keep it.
The eight styles explained
- UPPER and lower: every letter forced one way.
- Title Case: capitalises words but leaves minor words like of, the and and alone.
- Sentence case: capitalises after each full stop, question mark and exclamation mark.
- camelCase, snake_case and kebab-case: programming and URL conventions.
- aLtErNaTiNg: the sarcastic internet style, produced properly.
- All of them work on text of any length, live, with no upload.
The case you use is a signal
Text in the wrong case reads as careless even when the words are right. A heading in all capitals looks like shouting and is measurably slower to read, because the even rectangle of capital letters removes the word shapes readers rely on. A sentence with no capital at the start reads as a text message. A variable name in the wrong convention flags a developer as unfamiliar with the codebase.
None of these are hard to fix, but retyping is a waste of time and introduces new typos. Converting takes a second and preserves the words exactly.
Title case is the one that has rules
Most people capitalise every word and call it title case. Standard style guides do not: articles, coordinating conjunctions and short prepositions stay lowercase unless they begin or end the title. "The Lord of the Rings" is correct; "The Lord Of The Rings" is not.
This tool applies that convention using a list of the common minor words, a, an, the, and, but, or, of, in, on, to, for, at, by and similar, while always capitalising the first and last word. House styles disagree at the margins, particularly over prepositions of four or more letters, so check the result against your own guide if you have one.
The programming cases
- camelCase: variables and functions in JavaScript, Java and C#.
- snake_case: variables in Python and Ruby, and most SQL column names.
- kebab-case: CSS class names, URL slugs and HTML attributes.
All three take the same input and split it into words first, which means the converter handles a phrase, an existing camelCase name or a snake_case name equally well. Converting helloBigWorld to snake_case gives hello_big_world rather than one long lowercase run, because the boundary between a lowercase letter and a capital is treated as a word break.
Sentence case and what it cannot know
Sentence case lowercases everything, then capitalises the first letter and anything following a full stop, question mark or exclamation mark. That is correct for ordinary prose and wrong for proper nouns, names, places, brands and the word "I" all get lowercased and have to be fixed by hand.
There is no way around this without a dictionary of every proper noun in every language, so treat sentence case as a first pass on a document typed in capitals rather than a finished result. It still saves most of the work.
Practical uses
The common ones are rescuing a document typed with caps lock on, normalising a spreadsheet column of names before import, generating URL slugs from headings, and converting variable names between languages. If the text also needs deduplicating or sorting afterwards, the text sorter and duplicate line remover take the output directly. Everything runs in your browser, so nothing is uploaded.