# Timestamps

There are a lot of timestamps found across entities and it can admittedly get quite confusing.

# Timestamp format

All dates use the Internet date/time format as defined in RFC 3339, in the UTC timezone when not specified.

For example, 1985-04-12T23:20:50.52Z represents:

This date is present on all resources, it represents the instant when the resource was originally created.

This date is present on all resources, it represents the instant when the resource was last updated.

The following table explains the relationship between these two and the various possible states of a chapter:

Possible	PublishAt	ReadableAt	ExternalUrl	Result
Yes	Future	Past	`null`	Chapter will be readable on MangaDex at `publishAt`, but is not readable at all yet
Yes	Future	Past	non-`null`	Chapter will be readable on MangaDex directly at `publishAt`, but is for now just an external link
Yes	Past	Past	`null`	Chapter is readable on MangaDex, and has no external site link
Yes	Past	Past	non-`null`	Chapter is readable on MangaDex, and also contains a link to an external site

Note that publishAt may be set extremely far in the future as a way to say "it will always only be just a link".

This date is present on chapter resources and represents the instant when the content will be available directly on MangaDex.

Before that time, the chapter will be visible but not readable directly
- If the chapter has a non-null externalUrl, then it will be link before being readable
- If the chapter has no externalUrl, then it will only be displayed in the chapter lists

This date is present on chapter resources and represents the instant when the chapter is "readable" at all.

That is, whether it's an external chapter or an internal chapter whose pages are now available directly on MangaDex.

If publishAt is in future & chapter has externalUrl then readableAt is equals createdAt date
Otherwise readableAt is equals publishAt date