In standard English sentence casing (also referred to as "down style" in publishing), only the initial word of a sentence and proper nouns are capitalized. Both the Chicago Manual of Style and the Associated Press (AP) Stylebook mandate capitalizing:

• The first word following a terminal period (.), exclamation mark (!), question mark (?), or ellipsis (…).
• The standalone first-person subjective pronoun I and its contracted forms (e.g., I'm, I've, I'll, I'd).
• The first word inside full quoted sentences or dialogue (e.g., She asked, "Are we ready?").

Naive converters mistakenly capitalize words after any period. Our NLP-inspired regex tokenizer isolates common abbreviations such as Dr., Mr., Ms., Prof., e.g., i.e., vs., Inc., and etc. so they do not trigger unintended sentence breaks.

For instance, the phrase "Dr. Smith visited the lab vs. the clinic." remains intact without turning "Smith" or "The" into arbitrary sentence breaks.

Psychological reading studies confirm that reading text in ALL CAPS slows reading speed by up to 14–20%. Uniform rectangular word contours eliminate the ascenders and descenders (like h, t, d, p, y, g) that human eyes use to rapidly scan and identify words. Converting accidental CAPS-LOCK text or legacy database dumps into clean sentence case restores optimal readability and eliminates digital "shouting".

Your privacy is absolute. All sentence tokenization, capitalization algorithms, and file downloads are executed entirely within your browser's JavaScript engine. Zero text, drafts, confidential documents, or personal credentials are sent to our servers or third-party APIs.