Sentence Case Converter
Sentence case means: start each sentence with a capital letter, keep most other letters lowercase, and capitalize proper nouns and the pronoun “I” where the tool can recognize them. It is the default voice of emails, articles, support docs, and most product UI because it reads closest to how people speak.
Sentence case converter: fix ALL CAPS, messy paste, and uneven capitals
Sentence case means: start each sentence with a capital letter, keep most other letters lowercase, and capitalize proper nouns and the pronoun “I” where the tool can recognize them. It is the default voice of emails, articles, support docs, and most product UI because it reads closest to how people speak. Use this page when you inherit text from PDFs, chat logs, or legacy systems that broke capitalization. Paste the block, review the output, and copy or download. For headlines rather than paragraphs, our title case converter is usually the better fit.
What sentence case is (and is not)
Sentence case is not the same as “lowercase everything.” It restores structure: after a period, question mark, or exclamation point, the next letter should capitalize. It is also not title case, which would capitalize most words in a heading. Think of sentence case as how a well-edited paragraph in a novel looks. Automatic converters infer sentence boundaries from punctuation. Abbreviations like “e.g.” or “U.S.” can sometimes confuse naive tools; if your text is full of dotted acronyms, skim the output before publishing. For UI microcopy lists without punctuation, sentence case may be overkill—use our lowercase converter or edit manually.
Why product teams standardize on sentence case
Design systems from major tech companies popularized sentence case for buttons, menu items, and empty states because it feels conversational and reduces visual noise next to user-generated content. Title case every button can feel like shouting; sentence case matches how people describe actions in natural language. If you are auditing an old app, export strings, run them through this converter, then re-import—faster than retyping hundreds of labels. Pair the pass with a glossary so product names and trademarks stay exactly as legal approved.
Email, support tickets, and internal wikis
Customer messages often arrive in all caps when someone has caps lock on or is frustrated. Before you forward internally, converting to sentence case (with light editing) can make quotes easier to read while preserving the original in your help desk. Internal playbooks and Notion pages copied from slide decks frequently mix cases. A sentence-case pass plus a quick read fixes 80% of issues; use title case only on actual document titles afterward.
When to switch to title case instead
Use title case for article headlines, webinar titles, and chapter names when your brand follows that convention. Use sentence case for the paragraphs underneath. Many blogs show title case H1s with sentence-case body text—that pairing is a deliberate hierarchy. Our internal links connect both tools so you can jump from this page to the title case converter when you finish polishing the body and still need the headline formatted.
Newsletters, Markdown, and plain-text pipelines
Email platforms that strip formatting sometimes leave writers with plain text that alternates between shouty subject lines and timid body copy. Sentence case gives you a neutral baseline before you add bold or links in the WYSIWYG layer. Paste the entire draft, split the subject line out if you prefer title case there, and process each chunk with the right tool. Markdown writers often type in sentence case naturally, but imported RSS excerpts or cross-posted Medium articles may arrive half capitalized. Running the body through this converter before you commit to Git keeps diffs readable and avoids nitpicky review comments about stray capitals.
Examples
- HELLO. THIS WAS TYPED IN CAPS. → Hello. This was typed in caps. (Two sentences fixed)
- first sentence. second sentence. → First sentence. Second sentence. (Leading capitals)
- i think we should ship friday → I think we should ship friday (Capital “I”)
- MIXED Case WiTh noise → Mixed case with noise (Broad cleanup (verify proper nouns))
Frequently asked questions
Will proper nouns always stay correct?
Algorithms guess from patterns but cannot know every brand name. Always proofread people, product, and place names after conversion.
How does this handle bullet lists?
If each line ends with punctuation, many lines behave like sentences. For single phrases without periods, results vary—preview before publishing.
Is sentence case better for accessibility?
Long passages in all caps are harder to read; sentence case (or mixed case) generally improves readability for body content.