Get your whole audience's engagement over time

GET

/api/v3/contacts/engagement-timeline

const url = 'https://api.tryletterhead.com/api/v3/contacts/engagement-timeline?api=true&dateFrom=example&dateTo=example';
const options = {method: 'GET', headers: {Authorization: 'Bearer <token>'}};

try {
  const response = await fetch(url, options);
  const data = await response.json();
  console.log(data);
} catch (error) {
  console.error(error);
}

curl --request GET \
  --url 'https://api.tryletterhead.com/api/v3/contacts/engagement-timeline?api=true&dateFrom=example&dateTo=example' \
  --header 'Authorization: Bearer <token>'

Returns your whole company audience’s daily unique-engager rates (open / click / click-to-open / bounce) across a date window — the “Everyone” default of the engagement-over-time chart. For a single saved segment’s series, use Get a segment’s engagement over time.

This is a company-level (v3) read. Authenticate with a company API key as a Bearer token.

Authorizations

bearerAuth

Parameters

Query Parameters

api

required

boolean

Set to true.

dateFrom

required

string

Start of the window (inclusive), e.g. 2026-06-01.

dateTo

required

string

End of the window (inclusive). Must be on or after dateFrom.

channel

string

Restrict the timeline to the given channel identifier (slug).

Responses

200

200 OK

application/json

object

items

Array<object>

object

date

string

deliveredContacts

integer

uniqueOpeners

integer

uniqueClickers

integer

bouncedContacts

integer

openRate

number

clickRate

number

clickToOpenRate

number

bounceRate

number

message

string

total

integer

Example

{
  "items": [
    {
      "date": "2026-06-07",
      "deliveredContacts": 21400,
      "uniqueOpeners": 9800,
      "uniqueClickers": 1220,
      "bouncedContacts": 68,
      "openRate": 45.8,
      "clickRate": 5.7,
      "clickToOpenRate": 12.4,
      "bounceRate": 0.3
    },
    {
      "date": "2026-06-14",
      "deliveredContacts": 21650,
      "uniqueOpeners": 10120,
      "uniqueClickers": 1340,
      "bouncedContacts": 54,
      "openRate": 46.7,
      "clickRate": 6.2,
      "clickToOpenRate": 13.2,
      "bounceRate": 0.2
    }
  ],
  "message": "Audience engagement timeline retrieved.",
  "total": 2
}

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