Capitalizer

Capitalizer is a software component, utility, or function that applies capitalization rules to text. Its primary purpose is to convert text to a standardized case, often turning all letters to uppercase, but more commonly applying format-specific capitalization such as title case or sentence case.

It can operate in several modes: all-caps, title case (capitalizing major words while leaving minor words in lower case per style guides), and sentence case (capitalizing the first letter of each sentence). Some capitalizers preserve or detect proper nouns, acronyms, and hyphenated terms to avoid altering recognizable forms.

In computing, capitalizers appear as libraries in programming languages (for example, string methods toUpperCase in JavaScript or Python's .capitalize() and .title()), standalone command-line utilities, or integrated into text editors and content management systems. They may be locale-aware, respecting language-specific rules for capitalization, punctuation, and capitalization of initials.

Automatic normalization can mis-handle acronyms, initialisms, brand names, or terms with non-Latin scripts; context-sensitive capitalization is challenging.

Used for data cleaning, UI text normalization, preparing headlines, or ensuring consistency across documents.

See also: case conversion, capitalization, typography, text normalization.