Naming Files & Folders

Your web files will be viewed by numerous users who use a wide variety of operating systems (Mac, Windows, and Linux for instance) and devices (desktops, tablets, and smartphones are some examples). Therefore, it is essential to play it safe and avoid common illegal directory and filename characters.

Naming conventions are important in web folders as well as for downloadable files such as PDFs, Word documents, and Excel spreadsheets.

Do not use any of these common characters/symbols in filenames and folders:

Characters/Symbols

# pound

< left angle bracket

$ dollar sign

% percent

> right angle bracket

! exclamation point

& ampersand

* asterisk

' single straight quotes

{ left bracket

? question mark

" double straight quotes

} right bracket

/ forward slash

: colon

back slash

blank spaces

@ at sign

Also, keep these rules in mind:

  • Don’t start or end your filename with a space, period, hyphen, or underline.

  • Keep your filenames to a reasonable length and be sure they are under 31 characters.

  • Most operating systems are case sensitive; always use lowercase.

  • Avoid using spaces; use a hyphen or underscores instead.

Bad Filenames

What Web Browsers See

My Project Name.html

My%20Project%20Name.html

My PDF File#Name.pdf

My%20PDF%20File%23Name.pdf

Good Filenames:

  • index.html

  • my-pdf-file-name.pdf

Note: This list is not exhaustive. It is meant to help you avoid common errors in filenames. If you have any questions or need any assistance, do not hesitate to contact webmaster@cmoa.org.

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