File Management

Names and naming conventions

Learn how to establish file-naming conventions, best practices for formatting names, and what's in a name (elements to include in names and how to keep things sorted). Formatting redux offers a deep dive into why the recommendations on this page work.

File-naming conventions

A file-naming convention is a set of rules that govern how files and folders are named. Establishing a file-naming convention ensures compatibility and comprehension when working alone and in teams.

1. Determine what information is the most important to include in file names.
   • Different file types often require different information to be identifiable and useful.
   • Take your user's needs into consideration. Are they likely to search or files things by project name, identifiers, dates, etc.?
2. Choose a standard order for the selected components where the most important elements come first to facilitate sorting. 
3. Establish formatting rules for sequences and dates.
   • Use leading zeros, and ISO 8601 for dates (e.g., YYYY-MM-DD).
4. If multiple versions of files will be kept establish a suffix to identify different versions
   • e.g., _01, _v1, _draft, _final, etc.
5. Decide on standards for abbreviations and codes then document them in a README (see Documentation).
   • e.g., "department" should be abbreviated "dept"; QX = quarterly, etc.
6. Record the file naming schemas in a file system table (see Documentation) so you don't forget.

Formatting names

These practices will ensure the highest level of compatibility across systems, software, and applications.

• Keep names short, 32 characters or less.
• Use only Latin alphanumeric characters (A-Z, a-z, and 0-9), hyphens (-), and underscores (_).
• Do not use spaces. Separate components with hyphens, underscores, or letter case.
  • Keep letter case consistent as not all systems preserve case
  • Be aware that letter case separation (ex: camelCase) makes it hard to search for files.
• Do not use special characters, including en (–) and em (—) dashes.
• Do not use punctuation marks (! @ # $ % & * ( ) = + [ ] { } \ | : ; ' " , < > / ?).
  • A period should only be used to precede a file extension, never as a separator.
  • Exceptions: Hyphens and underscores are acceptable.

What's in a name?

This section is a more in-depth look at how to use file and folder names help us organize and locate digital content. Topics covered include what elements to include in names, and more details about how to get file names to sort well.

File names are descriptive

Files names help you identify what is inside a file and how it differs from similar files. You should name files based on important elements such as:

• Contents, what's inside? (e.g., tax form.pdf)
• Purpose, what is it used for? (e.g., completed tax form.pdf)
• Date, when was it made or altered? (e.g., 2023 completed tax form.pdf)
• Relationships, how does it relate to other files? (e.g., 2023 tax form amended 2024-08.pdf)

Folder names are categories

Folder names are categorical and should describe groups of files. Simple or broad categories work best, and you should name folders based on important elements such as:

• Subject matter, what are the files about? (e.g., 📁 my pets) 
• Type, what kind of files are inside? (e.g., 📁 photos )
• Purpose, how are the files used? (e.g., 📁 vet visit notes)
• Date, when where the files made or altered? (e.g., 📁 photos 2023)
• Relationships, how does this folder relate to the folders on the same level and to those above and below it? (e.g.,📁 my pets → 📁 photos → 📁 2017, 📁 2021, 📁 2022)

As the relationship example shows, folder names inherit topic and name associations from the folders above them. Making good use of these relationships is especially important in a browse file system (see Systems and theory). File and folder names can also share name elements to make relationships more explicit and to remind users which folder they are working in (e.g., 📁 my pets → 📁 photos → 📁 2017 → 🖼 2017 halloween pets.jpg).

Sorting

The following practices will keep your files in order, literally. 

• Alphabetical:
  • English language characters (A-Z, a-z) will sort dependably across operating systems, but characters from other alphabets may not unless the operating system is set to the same language.
  • Older operating systems and less sophisticated programs may not support additional languages and alphabets.
• Dates: Use ISO 8601 formatting, i.e. YYYY-MM-DD or YYYYMMDD.
  • Use numbers only, do not spell out the names of months.
  • Names that use this format will sort chronologically, both ascending and descending. 
• Numbered Series: Use leading zeros to maintain a consistent sort order. 
  • e.g., file_001.tif, file_003.tif, and file_021.tif will sort sequentially, but file_1.tif, file_21.tiff, and file_3.tif do not as numbers in file names are read as characters, not numerical values.
• Type, subject, or category: Put the most important or identifying elements first.
  • e.g., it's easy to separate cat files from the dog files when "cat" or "dog" is the first element in a file name (cats_01, cats_02, dogs_01, dogs_02); however, if the series number is more important, that should come first (01_cats, 01_dogs, 02_cats, 02_dogs).
  • If you have three or more name elements, the order of the elements becomes increasingly important for maintaining a useful sort order.

Formatting redux

A deep dive into why the naming recommendations on this page work.

Alphanumeric characters

When computer memory and storage were more restricted and expensive, the symbols (characters) used to interact with them were minimal. Since the majority of computer users during this time (1950-1980s) were English speakers, and the Latin alphabet was small (26 characters), it became the dominant character set and today's computers have inherited this legacy.

While most systems and programs now use UTF-8 or UTF-16 character sets, which support multiple alphabets and thousands of characters, the limited Latin alphabet character sets are still in use and restrict compatibility. Special characters such as arrows (→), superscripts (²), emojis (😮), percent signs (%) and most punctuation marks should be avoided for this reason and because some of them may function as Reserved characters (see section below).

Character separation

A space character in computer programming languages indicates the start of a new command, so filenames with spaces are cut off at the first space unless extra steps are taken. This is why spaces are not recommended even though they're the easiest way to separate name elements. However, spaces are often preferred by people with low-vision or dyslexia because they're easier to read, and they can be used safely in most modern systems. User preference is often the biggest factor in determining their use or replacement.

The best replacements for spaces are hyphens (-) or underscores (_) since some system treat all three characters (hyphen, underscore, and space) the same for search purposes. Spaces are also not supported in URLs (hyperlinks) so hyphens and dashes should be used when creating webpages. CamelCase, where letter case is used to separate words and name elements, is common but is not the best replacement for a space since letter case isn't considered in searches and it can be hard to read. 

Reserved characters

Reserved characters are characters that cannot be used in file and folder names because they have been assigned a specific function by the operating system. Some of the most common reserved characters are: backslash (\), forward slash (/), colon (:), asterisk (*), quotation mark ("), brackets ([ ]), period (.), and less than (<) and greater than (>) signs. Including these characters in filenames limits compatibility between systems. For example, Mac OS 9 and above supports a number of characters that are reserved characters for Windows (such as / \ : * ? < > |). This causes errors when downloading, sharing, or moving files across systems so it is best to avoid using these characters.

Short names

There is a hard limit on the number of characters in a file path. A file path is the route or description of where a file is located on your hard drive and folder structure. It includes the drive name, the names of all higher-level folders, and the file name.

For example, the file path to an image named "card-01" stored in your downloads folder might look like:
C:\Users\[account name]\Downloads\card-01.jpg

This is a short file path, only 44 characters long, but a complex folder structures and/or long file names can easily max out the limit of 260 characters on Windows and 255 characters for Mac OS. This is why short file and folder names are desirable - exceeding the limit will prevent you from being able to open or find your files and folders.

The limit (MAX_PATH) in Windows can be overridden but it is very risky to do so as can cause file storage (hard drive) and file write/read (software) errors. Use at your own risk.