Sentence Case Generator
Convert text to sentence case. The first word of every sentence is capitalized, the rest is lowercase, and common proper nouns (people, places, days, months, the pronoun I) stay capitalized. Useful for APA reference titles, academic prose, and any body text that needs the standard sentence-style cap.
How to use the sentence case generator
1. Paste your text
Drop any string into the input box. UPPER CASE rants, Title Case headlines, MiXeD CaSe nonsense, or all-lowercase notes all convert. The output panel updates on every keystroke.
2. Pick a mode
"Sentence case" is the default: first word of every sentence capitalized, the rest lowercase, common proper nouns preserved (people, places, days, months, the pronoun I). Three other modes sit alongside: lower case, UPPER CASE, Title Case.
3. Copy the output
The Copy button puts the converted text on your clipboard. Paste it into a doc, an email, an APA reference, or a comment thread.
When you need sentence case
APA reference titles
APA 7th edition uses sentence case for the titles of journal articles, book chapters, and reports in the reference list. "The role of attention in working memory" - not "The Role of Attention in Working Memory". This generator handles the exact rule. See also: essay word counter.
Body copy after pasting from an all-caps source
Email blasts, press releases, and pasted-from-Word documents sometimes arrive in ALL CAPS. Drop them into the tool and get clean sentence case in one click. Punctuation and spacing are preserved.
Academic prose normalization
Student essays sometimes arrive with title-case section headings ("In Conclusion, The Author Argues...") that should be sentence case. One paste and one copy fixes it.
YouTube and forum comments
Casual comments often arrive in mixed case ("THIS is what I MEANT"). Sentence case makes them readable and professional.
Markdown and prose normalization
Markdown body text (paragraphs under H1/H2 headings) should be sentence case for readability. The tool runs the conversion in JavaScript so you can paste large documents without server-side latency.
What the tool capitalizes
Sentence case is not just "first letter, then lowercase the rest." A useful sentence-case engine has to handle:
- Sentence-initial capitalization: every period, exclamation mark, and question mark followed by whitespace triggers a capital on the next word.
- Paragraph-initial capitalization: every newline followed by text triggers a capital.
- The pronoun I: always capitalized, even mid-sentence. The tool preserves "I", "I'm", "I've", "I'll", "I'd".
- Days of the week and months: Monday through Sunday, January through December. Always capitalized.
- Common proper nouns: a curated list of around 80 names (people, places, brands) the tool restores after lowercasing. Mary, John, Paris, London, Google, Apple, and similar.
If your text contains proper nouns not in the list (rare names, niche brand names, technical terms), the tool will lowercase them. You can fix those by hand in the output box, then copy.
Sentence case vs title case (the difference matters)
Two different conventions. Confusing them is the most common formatting error in academic writing.
| Convention | Rule | Used for |
|---|---|---|
| Sentence case | Capitalize first word + proper nouns. Lowercase the rest. | APA reference titles, body copy, modern minimalist headlines. |
| Title case | Capitalize all major words. Lowercase articles, short prepositions, conjunctions. | Book and article titles, news headlines, MLA reference titles. |
APA 7th uses sentence case for references but title case in the body when citing an article title in-text. MLA uses title case for everything. Chicago has its own variant (capitalize all words 5+ chars). For title case across style guides, use the Title Case Converter.
Related tools
Frequently asked questions
What is sentence case?
Sentence case capitalizes the first word of every sentence plus proper nouns. Everything else is lowercase. It is the standard for APA reference titles, body copy, and modern minimalist headlines.
What is the difference between sentence case and title case?
Sentence case capitalizes only the first word and proper nouns. Title case capitalizes all major words (nouns, verbs, adjectives) and lowercases articles and short prepositions. Use sentence case for APA reference titles and body copy; use title case for MLA references and most book/article titles.
Does the tool preserve proper nouns?
Yes, for common ones. A curated list of around 80 proper nouns (people names, place names, days, months, the pronoun I, big brands) is restored after lowercasing. Rare or niche proper nouns will be lowercased; you can fix those by hand in the output box.
Does the tool capitalize after a colon?
Not currently. The tool capitalizes after periods, exclamation marks, question marks, and newlines. APA 7th says to capitalize the first word after a colon when introducing an independent clause, but the rule is genre-specific; we leave it off by default to avoid over-capitalization.
Will my draft be sent to a server?
No. The conversion runs entirely in your browser. Nothing leaves this tab.
Does the tool handle abbreviations like U.S.A. or e.g.?
Partially. Periods inside abbreviations get treated as sentence-end markers by the simple regex used here, so 'U.S.A. policy' may render as 'U.S.A. Policy'. For abbreviation-heavy text, you may need to fix output by hand.
Can I use this for APA reference titles?
Yes. APA 7th specifies sentence case for journal article titles, book chapters, and reports in the reference list. Paste the title; copy the output; paste into your reference list.
What about contractions (I'm, don't)?
Contractions are preserved. 'I'm' stays 'I'm' (capital I preserved via the proper-noun list). 'Don't' becomes 'don't' (lowercased), unless it starts a sentence.
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