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Turn Any Text into Sentence Case Convert text to sentence case — capitalize the first letter of each sentence.

Sentence Case Converter illustration
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Sentence Case Converter

Convert text to sentence case — capitalize the first letter of each sentence.

1

Paste Your Text

Paste or type your text that needs sentence case formatting.

2

Review the Converted Text

See text converted with the first letter of each sentence capitalized.

3

Copy the Formatted Text

Copy the sentence-cased text to your clipboard.

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What Is Sentence Case Converter?

A sentence case converter formats text so that only the first letter of each sentence is capitalized, with the rest in lowercase. This is the most natural and commonly used capitalization style in English prose, matching how sentences are normally written. The tool detects sentence boundaries (periods, exclamation marks, question marks) and capitalizes the first letter after each one. It's useful for fixing text that's been typed in ALL CAPS, inconsistent capitalization, or when you need to normalize text to standard sentence formatting.

Why Use Sentence Case Converter?

  • Fixes ALL CAPS text into natural sentence formatting
  • Automatically detects sentence boundaries
  • Produces the most readable text formatting style
  • Essential for normalizing inconsistently formatted text
  • Preserves proper nouns when possible

Common Use Cases

Fix ALL CAPS Text

Convert text accidentally typed in caps lock to proper sentence formatting.

Content Formatting

Normalize body text from various sources to consistent sentence case.

Database Cleanup

Clean up user-generated content that may have inconsistent capitalization.

Email Formatting

Fix email text that was pasted in incorrect capitalization.

Technical Guide

Sentence case conversion first lowercases the entire text, then capitalizes the first letter after each sentence-ending punctuation mark (. ! ?) followed by whitespace. The algorithm preserves paragraph breaks and handles multiple consecutive punctuation marks. It also capitalizes the first letter of the text. The first character after newlines is also capitalized to handle multi-paragraph text correctly. The main limitation is proper nouns — the tool cannot automatically identify names, places, and other proper nouns that should remain capitalized, so some manual correction may be needed after conversion.

Tips & Best Practices

  • 1
    After conversion, review for proper nouns (names, places) that need re-capitalizing
  • 2
    Sentence case is the standard for body text in most English writing
  • 3
    Use this to quickly fix text pasted from all-caps sources
  • 4
    Some style guides prefer sentence case for headings and titles
  • 5
    Check for acronyms that should remain uppercase after conversion

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Frequently Asked Questions

Q What is sentence case?
Sentence case capitalizes only the first letter of each sentence and proper nouns, leaving all other letters lowercase. It is the standard format for regular text.
Q Does it preserve proper nouns?
The tool cannot automatically detect proper nouns. After conversion, you may need to re-capitalize names, places, and other proper nouns manually.
Q How does it detect sentences?
It looks for sentence-ending punctuation (periods, exclamation marks, question marks) followed by spaces to identify sentence boundaries.
Q Is sentence case the same as lowercase?
No, sentence case capitalizes the first letter of each sentence, while lowercase makes all letters small.
Q How do I choose between sentence case and title case?
Use sentence case for body text, paragraphs, and most UI labels. Use title case for headlines, book titles, and major headings.

About This Tool

Sentence Case Converter is a free online tool by FreeToolkit.ai. All processing happens directly in your browser — your data never leaves your device. No registration or installation required.