Useful timestamps

Most of our APIs, including Server API, Webhooks and JavaScript agent, support useful timestamps related to a visitor in the response formats. All these timestamps are presented as ISO-8601 strings (UTC timezone, millisecond precision). The majority of popular programming languages support ISO-8601 time format in their standard libraries.

Format

That's what those timestamps look like in the responses of the corresponding APIs:

{
  // ...
  "firstSeenAt": {
    "global": "2022-03-16T11:26:45.362Z",
    "subscription": "2022-03-16T11:31:01.101Z"
  },
  "lastSeenAt": {
    "global": "2022-03-16T11:28:34.023Z",
    "subscription": null
  },
  // ...
}

Definitions

• firstSeenAt.subscription - time of the first visit of the visitor within the current subscription.
• firstSeenAt.global - time of the first visit of the visitor across all subscriptions.
• lastSeenAt.subscription - time of the previous visit of the visitor within the current subscription.
• lastSeenAt.global - time of the previous visit of the visitor across all subscriptions.

Those timestamps can be equal to null. For instance in case a completely new visitor comes,
both lastSeenAt timestamps will be equal to null, because there is no previous visit before the first visit. In case a visitor comes for the first time within your subscription, but has been seen within another subscription, lastSeenAt.subscription will be null and lastSeenAt.global won't.

Both firstSeenAt timestamps are evaluated correctly for visitors that made their first visit after February 4th, 2022. If you see any firstSeenAt value earlier than or equal to February 4th, 2022, it might be not correct - a user could have done a visit even earlier than the presented firstSeenAt time shows.