Edited 6/19/05 2:20PM CST, 2nd version
FAQ #148: What are LiveJournal's limitations on data?
Links to information about specific features are in the "Further Reading" section at the bottom of the page.
USERNAMES AND PASSWORDS
Usernames are limited to 15 characters, and the characters that are allowed in usernames are a-z, 0-9, and the underscore (_). Capitalized letters and the hyphen (-) will be converted to lowercase and the underscore, respectively. Passwords are limited to 30 characters.
The limitations on the lengths of various input fields are as follows:
* Comments: 9,000 bytes or 4,300 characters
* Comment Subjects: 100 characters
* Custom Friends Group Names: 30 characters
* Entries: 65,535 bytes or characters
* Entry Properties (Currents): 255 bytes or 100 characters
* Entry Subjects: 255 bytes or 100 characters
* Memory Keywords: 40 characters, 5 keywords per memory
* Memory Titles: 80 characters
* Poll Names: 1000 characters
* Poll Questions: 1000 characters, maximum of 255 questions
* Poll Radio and Check Box Options: 500 characters, maximum of 255 options
* Poll Text Entry Responses: 255 characters
* User Picture Keywords: 40 characters, 5 keywords per picture
* User Picture Comments: 120 characters
Note that the web update page limits the entry properties so that "Current Mood" can only hold 30 characters and "Current Music" can only hold 60 characters. However, if you use a downloaded client that does not limit the length of these properties, you can fill in the entire 255 bytes or 100 characters.
EDIT PERSONAL INFORMATION PAGE
These limitations relate specifically to the Edit Personal Information page.
* Name: 50 characters
* E-mail: 50 characters
* Webpage URL: 255 bytes
* Webpage Name: 255 bytes
* AOL IM: 28 characters
* ICQ #: 12 characters (standard)
* Yahoo! ID: 33 characters (standard)
* MSN Messenger: 60 characters
* Jabber Address: 60 characters
* City: 60 characters
* State/Province/Territory: 50 characters
* About You: 65,535 bytes or characters
* Journal Title and Subtitle: 80 characters each
* Friends Page Title: 80 characters
Only the 75 most recent entries of your journal will display in the Most Recent view. You can change how many of those 75 entries display on a single page through the customization interface if you are using S2, or with the OPT_ITEMS override if you are using S1. This number per page can be anywhere from 1 to 50. However, if you attempt to navigate back further than 75 entries, your journal will begin to use the Day view.
The Month View (http://www.livejournal.com/users/exampleusername/2002/09/) can only display the first 2,000 entries made during that month. To access subsequent entries, navigate to individual Day Views, like the one linked to below.
The Day View (http://www.livejournal.com/users/exampleusername/2002/09/05/) can only display the first 200 entries made during that day. To access subsequent entries, use the "Previous" and "Next" arrow buttons found on individual entry pages.
When filtering your journal by tags, only the 100 most recent entries with that tag can be displayed.
You can only view up to the 50 most recent entries in a journal when you select the "X most recent entries" option at http://www.livejournal.com/editjournal.bml.
OTHER LIMITS ON ENTRIES
There are limits imposed upon the earliest and latest dates that you can post on LiveJournal, using the "Entry is Backdated" option. The earliest date posts are allowed to have is 1970-01-01, and the latest date is 2037-12-31.
The maximum number of comments that can be posted on any given entry is 5,000.
For a moderated community, there may only be a maximum of 50 posts waiting for approval at any one time. Additional posts will cause an error message to be displayed to the user attempting to post indicating that the queue is full. Also, each user may only have one post waiting for approval in any particular moderated community. Additional posts to a community from a user who already has a pending post for that community will cause the error message "Maximum queued posts for this community+poster combination reached" to be displayed to that user when posting.
LIMITATIONS ON OTHER FEATURES
Friends lists are limited as described in http://www.livejournal.com/support/faqbrowse.bml?faqid=61. The maximum number of custom friends groups you can have is 30.
Interests are limited as described in http://www.livejournal.com/support/faqbrowse.bml?faqid=60.
User pictures are limited as described in http://www.livejournal.com/support/faqbrowse.bml?faqid=1.
To-do list items are limited as described in http://www.livejournal.com/support/faqbrowse.bml?faqid=86.
Phone posts and transcriptions are limited as described in http://www.livejournal.com/support/faqbrowse.bml?faqid=183.
Link Lists are limited as described in http://www.livejournal.com/support/faqbrowse.bml?faqid=169.
The number of memories and memory keywords that you can have is unlimited.
The number of custom mood themes you can create is unlimited.
The maximum number of S2 styles you can have is 10.
Update Journal page
What is a downloadable client? Where can I get one?
Edit Personal Information page
Customize Journal interface
How do I change the number of journal entries per page?
What are tags? How do I use them?
How do I edit or delete a journal entry I wrote?
What is the "Entry is backdated" option? How do I use it?
What are custom friends groups? How do I use them?
What are "Memories"? How do I use this feature?
How do I create a custom mood theme?
How do I create a custom S2 style?
What are moderated communities? How do they work?
Comments or suggestions are definitely welcome.