NYnylas
Tracking events

Return an engagement summary

Changed on

Returns your open and click rates for a date window, compared with the previous window of the same length, with the counts behind them. Use it to see whether engagement is going up or down.

The open rate is the share of messages with open tracking that were opened at least once. Treat it as a trend rather than an exact count: some mail clients and privacy features load images automatically, which counts as an open. Messages count on the day they were sent, so rates for recent days keep rising as recipients open them.

get/v3/metrics/tracking/summary

Request

Query parameters

startstring date

The first day of the window, as a UTC date in YYYY-MM-DD format. Defaults to six days before end, so the default window covers 7 days. A window can cover up to 365 days.

endstring date

The last day of the window, as a UTC date in YYYY-MM-DD format. Defaults to today. Today is included as a partial day.

sending_domainstring

Return only data for messages sent from this domain.

Response

Success. Returns the summary.

request_idstring

The request ID.

Example response

{
  "data": {
    "totals": {
      "tracked_opens": 1200,
      "tracked_links": 1200,
      "opened": 384,
      "clicked": 96,
      "opens_total": 611,
      "clicks_total": 142
    },
    "metrics": {
      "open_rate": {
        "value": 98.6,
        "delta_pp": -0.8,
        "prior_value": 99.4
      },
      "click_rate": {
        "value": 98.6,
        "delta_pp": -0.8,
        "prior_value": 99.4
      }
    },
    "prior_period": {
      "start": "2026-10-24",
      "end": "2026-10-30"
    }
  }
}

Changes