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General rules

Use sentence-style capitalization. That means everything is lowercase except for the first word and proper nouns, which include the names of brands, products, and services.

  • Use sentence-style capitalization most of the time. That means:
    • Capitalize the first word of a sentence, heading, title (documentation only, marketing will use title case), UI label (such as the name of a button or check box), or standalone phrase.
    • Capitalize proper nouns.
    • Use lowercase for everything else.
  • Always capitalize the first word of a new sentence. Rewrite sentences that start with a word that’s always lowercase.
  • Don’t use all uppercase for emphasis. (It’s OK to use italic font sparingly for emphasis.)
  • Don’t use all lowercase as a design choice. Although all uppercase is used occasionally as a design element, don’t use it in text.
  • Don’t use internal capitalization (such as AutoScale or e-Book) unless it’s part of a brand name or UI term.
  • Don’t capitalize the spelled-out form of an acronym unless it’s a proper noun.
  • Don’t capitalize job titles/roles unless they precede a name. In general, titles that come before names are capitalized, and titles that come after names or are used as general terms are lowercase.
    • Correct: John Smith is the vice president.
    • Incorrect: John Smith is the Vice President.
    • Correct: Vice President John Smith.
    • Incorrect: BriteCore has many Independent Contractors.
    • Correct: BriteCore has many independent contractors.
  • Don’t capitalize general terms; only capitalize specific titles and names—proper nouns.
    • Incorrect: There are two instances in which Contractor Agreement Renewal is necessary.
    • Correct: There are two instances in which contractor agreement renewal is necessary.
    • Correct: Independent contractors must complete the Contractor Agreement each year. (This is the name of the form/policy/procedure.)
    • Incorrect: Independent contractors must complete the contractor agreement each year. (The names of a specific form/policy/procedure should be capitalized.)
    • Incorrect: Employees must sign an employee handbook each year. (An = not a specific handbook; thus, you know it’s not the title.)
    • Correct: Employees must sign the Employee Handbook each year. (The = a specific handbook; thus, you know it’s the title.)
  • When words are joined by a slash, capitalize the word after the slash if the word before the slash is capitalized.



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UI capitalization

Use the following capitalization guidelines when documenting UI elements:

  • For menu names, command names, command button names, dialog box titles, and tab names, follow the capitalization of the user interface. If the user interface is inconsistent, use sentence-style capitalization.
  • For labels in the user interface that are all lowercase or all uppercase, sentence-style capitalization is recommended.

See UI element conventions for more information on how to write and format UI elements.

File types and filename extensions

File types and file name extensions are often used interchangeably, but they aren’t quite the same thing.

File name extensions are the characters that appear at the end of a file name. Write file name extensions in lowercase, preceded by a period. Don’t write them in all caps.

Examples: .csv, .docx, .xlsx, .jpeg; not .CSV, .DOCX, .XLSX, .JPEG

File type, or file format, refers to a file’s coding. When you’re discussing a file type, or file format, use the formal name of the type. The file type name is often in all caps because many file type names are acronyms or initialisms. Do not use the file name extension to refer generically to the file type.

Usage examples

In the file name mydata.csv, the file name extension is .csv, indicating that this is a CSV file. Changing the file name extension from .csv to .mp3 doesn’t change the file type from CSV to MP3.

Select the button to download the PDF.

Make sure the file you’re uploading has the .xlsx file name extension, or the upload won’t work.

Make sure the file you’re uploading is an XLSX file, or the upload won’t work.


Use sentence-style capitalization in most titles and headings: capitalize the first word and lowercase the rest.


Proper nouns, including UI, brand, product, and service names, are always capitalized. If a title or heading includes a colon, capitalize the first word after it.

Titles of blog posts, documentation articles, and press releases use sentence-style capitalization.


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