Email Title Capitalization
Professional email subject lines use sentence case: only the first word is capitalised, along with proper nouns and acronyms.
Word-by-word explanation
Email capitalization rules
- Sentence case: only first word capitalised
- Proper nouns always capitalised
- Acronyms preserved
- All other words lowercase
- Conveys a professional, conversational tone
Read the full Email title capitalization rules with examples.
When to Use Email Title Capitalization
Email title case is the standard for Business Email, Newsletters, Marketing Emails, Transactional Email writing. Professional email subject lines use sentence case: only the first word is capitalised, along with proper nouns and acronyms. When your work will be reviewed, published, or cited within these fields, using the correct capitalization style shows attention to detail and compliance with professional standards.
Email Title Case vs Other Styles
Title capitalization is not universal. The same title formatted in Email style will look different from APA, Chicago, MLA, or AP — and each difference is intentional. Use the style comparison tool to enter your title and see all nine styles side by side. If you need to convert a large list of titles, the batch capitalizer handles CSV and TXT imports for bulk workflows.
How the Email Capitalizer Works
Paste your title into the tool above. Select Email as the active style and the result appears immediately. Click "Explain" to see the rule applied to each word. Use the copy button or press ⌘↵ to copy the output. Everything runs in the browser — no account, no signup, no data sent to a server.
Email capitalization FAQ
Most email best-practice guides recommend sentence case for subject lines — it feels more natural and personal. TitleCasePro's Email mode uses sentence case.
Studies from email marketing platforms like Mailchimp suggest sentence case and lower-case subject lines often achieve slightly higher open rates because they feel less like promotional blasts.
For professional and marketing emails, sentence case is the modern standard. Formal business letters and academic emails sometimes use title case.
Proper nouns, brand names, and acronyms are always capitalized even in sentence-case email subjects.