Sentence Case Converter

Automatic Capitalization / Truecasing


What does this converter do?

This converter capitalizes text in sentence case style, i.e., like regular sentences are conventionally capitalized: All words are lowercase, except for the first word, proper nouns, and proper adjectives (Wednesday, George, New York City, Spanish, …). Another way of looking at it is that the converter corrects or restores the capitalization of uncased or badly cased text.
For example, this converter corrects texts that were written in all lowercase. Another use case are legal documents such as end-user agreements, which are often written in all caps and thus hard to read. The sentence case converter can easily convert such documents into a readable form. Please note that the automatic capitalization of text is a difficult task, so achieving flawless results is not possible.
If you want to convert very long texts, and/or call the conversion from your own programs, have a look at the Sentence Case Converter API.

Using the sentence case converter

Type in the text to be converted, or paste from the clipboard. If the option “Convert when text is pasted” is active, then pasting text automatically triggers the conversion. If not, press the “Convert” button, or Ctrl+Enter (Cmd+Enter on a Mac). When the text has been converted, you can copy the results to the clipboard by clicking the “Copy” button, or by pressing Ctrl+C (marking the text is not necessary).
The following options are available:
  • Highlight changes: If this option is checked, all letters whose capitalization has changed are marked in orange.
  • Use straight quotes: If this option is not checked, quotation marks in the input text are converted to curly quotes, also known as smart quotes. If checked, straight quotes, also known as typewriter quotes, will be used instead.
  • Convert when text is pasted: If checked, then pasting text triggers the conversion. Clearing the text box before pasting is not necessary; present text will be replaced by the pasted text.


In Natural Language Processing (NLP), the task of correcting the capitalization of a text is known as truecasing, and a converter like this is called a truecaser. Truecasing is an important preprocessing or postprocessing step for NLP tasks such as machine translation, named entity recognition, and speech recognition. The Sentence Case Converter / Truecasing API offers a convenient way to perform this task.