Sentence Case
Convert text to sentence case so that only the first letter is capitalized and the rest remains consistently lowercase. Runs in your browser, GDPR-compliant.
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How to use this tool (video)
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Sentence Case
The sentence case converter turns text into sentence case so that only the first letter of each sentence is capitalized and the rest remains consistently lowercase. Ideal for text that needs to be professionally and readably formatted.
How it works
The converter analyzes the text and identifies sentence boundaries based on punctuation marks like periods, exclamation marks and question marks. After each punctuation mark the next letter is capitalized and all following letters until the next punctuation mark are set to lowercase. Consider a concrete example: The text "hello world. how are you today? i am fine" becomes "Hello world. How are you today? I am fine". Every sentence starts with a capital letter and the rest stays lowercase. Umlauts like a, o and u are not altered and their capitalization is only changed if they appear at the start of a sentence.
What the tool can and cannot do
The tool can format text into proper sentence case by capitalizing the first letter of each sentence and lowercasing the rest. It recognizes sentence boundaries based on common punctuation and processes German and English text equally. However, it cannot correctly capitalize proper nouns and names. Names like "Müller" or "Berlin" are not recognized and may be lowercased if they do not appear at the start of a sentence. The tool is a formatting utility, not a spell checker or editor. It does not correct grammar errors and does not alter meaning.
Why local processing in the browser
All formatting happens locally in your browser. Your text never leaves your device and is never sent to a server. There is no upload, no server log files and no third party access. You need no account and no registration. After the page loads, the converter works offline because the required resources are cached in the browser. There is no server that could be attacked and nothing is transmitted over the network. You can format as many texts as you like and discard results at any time.
Frequently asked questions
What happens to proper nouns in sentence case?
Proper nouns cannot be recognized by the converter and may be lowercased if they do not appear at the start of a sentence. The tool is a formatting utility, not a spell checker.
Do I need to be online?
No, after the page has loaded once, the converter works offline. The required assets are cached and a flaky connection will not interrupt you.
Are my data uploaded?
No, your text is never sent to a server. Everything is processed locally in your browser with no upload and no third party.
Does the tool work with German sentences?
Yes, the converter recognizes sentence boundaries based on periods, exclamation marks and question marks and works equally well with German and English text.
Can abbreviations be handled correctly?
Abbreviations with a period are recognized as sentence boundaries and the next letter is capitalized. This can sometimes lead to unexpected results.
Is this tool free to use?
Yes, the sentence case converter is a free tool that runs directly in your browser. There are no hidden costs or limitations.