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Case converter

Convert text to UPPERCASE, lowercase, Title Case or Sentence case.

Related tools

All Transform & clean tools →
Alternating case (mocking) generatorTurn text into aLtErNaTiNg CaSe for the mocking meme style.Toggle caseSwap uppercase to lowercase and vice versa for every letter.Sentence case converterCapitalize the first letter of every sentence in your text.Add line numbersPrefix every line of your text with a sequential line number.Alphabetize wordsSort all the words in your text into alphabetical order.Bionic reading converterTurn any text into bionic reading format, which bolds the first part of each word so your eye can move faster while the brain fills in the rest. Adjust the fixation strength, see a live styled preview, and copy a Markdown version to paste anywhere that supports bold.Comma-separated ↔ linesConvert a comma-separated list into lines, or lines back into a comma list.Palindrome checkerCheck whether your text reads the same forwards and backwards.

Case converter is free to use as often as you like, directly from this page. You will find it under Transform & clean, with Alternating case (mocking) generator and Toggle case for the neighbouring cases.

How to use it

  1. Open the tool — no signup or install needed.
  2. Enter your input or adjust the available options.
  3. Get your result instantly, then copy or download it.

Frequently asked questions

What does Case converter do?

Convert text to UPPERCASE, lowercase, Title Case or Sentence case.

When would I actually use this?

Cleaning up a paste before it goes anywhere: stripping duplicates from a list, normalising case, removing accents for a filename, or sorting lines.

What is the most common mistake?

Sorting text as if it were ASCII. Accented letters land after Z in a byte sort, which puts "Zurich" before "Émile" and produces a list no reader will accept.

How is Case converter different from Alternating case (mocking) generator?

They sit next to each other but answer different questions: Alternating case (mocking) generator is the one to open when you need it to turn text into aLtErNaTiNg CaSe for the mocking meme style. Pick whichever matches what you're starting from — both are free.

Is there a tool for the next step?

Toggle case is the closest one after this: Swap uppercase to lowercase and vice versa for every letter.

Where do the figures come from?

Transformations use the browser's Unicode-aware string handling, so case changes and sorting respect the locale rather than byte order. Nothing is truncated: what comes out is the whole of what went in.

Further reading

All guides →
ExplainerSentence Case and Title Case: The Rules Differ by LanguageEnglish title case has three different cutoffs depending on the style guide. French, Spanish, Portuguese and Italian have none at all. German capitalises every noun. The tool knows about none of this — here is exactly what it does.ExplainerRemoving Accents Breaks Search — Until You Do It on Both SidesFolding diacritics is a normalisation step, and normalisation only works when the same function runs on the index and on the query. NFC against NFD with the code points shown, and the letters — ø, ł, ß, œ, ı — that survive the strip untouched.How-toNumbering the Lines of a Text for a Review with Several PeopleNumbering starts at 1 and cannot be set to 0, the alignment is spaces rather than zeros, and the remover undoes eight of the eleven separators without touching the indentation. What it still cannot do is tell your numbers from its own.ExplainerWhat a Palindrome Checker Has to Decide Before It Can AnswerCase, whitespace, punctuation and diacritics: four policies, six real sentences, and the answer changes with each one. Then the harder half — reversing a string is itself undefined, and code-unit reversal breaks emoji and detaches accents, demonstrated in Node.ExplainerSorting Text Is Not One Operation: Four Orderings That All Call Themselves AlphabeticalCode-unit order, natural order and locale collation run on the same list in Node, with the outputs printed. Why Zebra beats apple, why item10 beats item9, and why ä sits next to a in German but after z in Swedish.ExplainerDetecting the Language of a Text, and Why Short Texts FailMeasured, not asserted: 90 short real phrases across six languages, none declined and 68 right — 76%, falling to 64% under sixteen letters. Four of the wrong answers came back at 100% confidence.