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Get aggregate outbound SMS statistics

GET
/v1/sms/stats/summary
const summary = await bird.sms.stats.summary({
  from: "2026-05-01", // both calendar days for a day window, or
  to: "2026-05-31", //   both RFC 3339 instants for an hour window
});
console.log(summary.delivery, summary.latency);
Response200
{
  "period": {
    "from": "2026-05-01",
    "to": "2026-05-25",
    "data_as_of": "2026-05-25T14:03:10Z"
  },
  "delivery": {
    "accepted": 14820,
    "sent": 14810,
    "delivered": 14720,
    "undelivered": 60,
    "failed": 25,
    "rejected": 10,
    "expired": 5,
    "delivery_rate": 0.9932,
    "failure_rate": 0.0061
  },
  "latency": {
    "processing": {
      "p50_ms": 420,
      "p95_ms": 1820,
      "p99_ms": 4920
    },
    "delivery": {
      "p50_ms": 420,
      "p95_ms": 1820,
      "p99_ms": 4920
    },
    "total": {
      "p50_ms": 420,
      "p95_ms": 1820,
      "p99_ms": 4920
    }
  },
  "comparison": {
    "period": {
      "from": "2026-05-01",
      "to": "2026-05-25",
      "data_as_of": "2026-05-25T14:03:10Z"
    },
    "delivery": {
      "accepted": 14820,
      "sent": 14810,
      "delivered": 14720,
      "undelivered": 60,
      "failed": 25,
      "rejected": 10,
      "expired": 5,
      "delivery_rate": 0.9932,
      "failure_rate": 0.0061
    },
    "latency": {
      "processing": {
        "p50_ms": 420,
        "p95_ms": 1820,
        "p99_ms": 4920
      },
      "delivery": {
        "p50_ms": 420,
        "p95_ms": 1820,
        "p99_ms": 4920
      },
      "total": {
        "p50_ms": 420,
        "p95_ms": 1820,
        "p99_ms": 4920
      }
    },
    "delta": {
      "accepted_pct_change": 0.508,
      "sent_pct_change": 0.121,
      "delivered_pct_change": 0.122,
      "undelivered_pct_change": -0.031,
      "failed_pct_change": -0.018,
      "rejected_pct_change": 0,
      "expired_pct_change": 0.04,
      "delivery_rate_pp": 0.004,
      "failure_rate_pp": -0.0008
    }
  }
}

Returns one aggregate row for the requested period. It includes SMS lifecycle counts, delivery and failure rates, and processing, delivery, and total latency percentiles (p50, p95, and p99). Rows use send-time attribution, so recent periods can under-report delivered while delivery reports arrive.

Rate fields are null when their denominator is zero. For example, delivery_rate is null when no message was accepted.

from and to must both be days or RFC 3339 instants. Day windows cover up to 365 days. Instant bounds round down to the hour and may span up to 720 hours. Mixing the forms returns 422. Set timezone for local boundaries, one dimension filter at most, or compare=previous_period for the preceding equal-length window.

Query Parameters

fromstring

Inclusive start of the window: a calendar day (YYYY-MM-DD) or an RFC 3339 instant rounded down to the hour. The timezone parameter makes a calendar day local and rounds an instant down to the local hour. Omit timezone to use UTC. When timezone is set, a numeric UTC offset such as +05:45 is rejected; use a calendar day or a Z (UTC) instant. This value must use the same form as to. When omitted, it defaults to 30 days before to for day windows or 168 hours (7 days) before to for hour windows.

tostring

Inclusive end of the window: a calendar day (YYYY-MM-DD) or an RFC 3339 instant rounded down to the hour. The timezone parameter makes a calendar day local and rounds an instant down to the local hour. Omit timezone to use UTC. When timezone is set, a numeric UTC offset is rejected; use a calendar day or a Z (UTC) instant. This value must use the same form as from. When omitted, it defaults to today for day windows or the current hour for hour windows in that timezone. Day windows may not exceed 365 days; hour windows may not exceed 720 hours (30 days).

timezonestring

IANA timezone identifier used to group statistics, for example Asia/Kathmandu. The default is UTC. Day and hour boundaries, including the default window when from and to are omitted, follow this timezone. When this parameter is set, pass from and to as calendar days or Z instants instead of timestamps with explicit UTC offsets.

originatorstring

Restrict the statistics to a single originator (the sender address messages were sent from). Mutually exclusive with the other dimension filters (country, category, carrier); only one may be set per request. Matches the message from.

countrystring

Restrict the statistics to a single destination country, as an ISO 3166-1 alpha-2 code. Mutually exclusive with the other dimension filters (originator, category, carrier); only one may be set per request.

categorystring

Restrict the statistics to a single category. Mutually exclusive with the other dimension filters (originator, country, carrier); only one may be set per request.

carrierstring

Restrict the statistics to a single delivery carrier. Mutually exclusive with the other dimension filters (originator, country, category); only one may be set per request.

comparestring

Set to previous_period to also include the same statistics for the immediately preceding window of equal length, plus the change between the two, so you can show "+X% vs last period" without a second request.

Possible values: previous_period

Response Payload

period
object
required

The window the response covers (echoed back from the request, day or hour grain), plus data_as_of, the freshness boundary the data is current to.

Show child attributes
delivery
object
required

SMS lifecycle counts and rates for a whole period or breakdown. Counts use the message send time, so a later delivery stays attributed to the bucket in which the message was sent. Rates are null when their denominator is zero.

Show child attributes
latency
object
required

Latency percentiles in milliseconds for the requested scope:

  • processing: From acceptance to carrier handoff.
  • delivery: From carrier handoff to delivery confirmation.
  • total: From acceptance to delivery confirmation.

Each family is omitted when no qualifying event contributes a measurement. Individual percentiles can also be null.

Show child attributes
comparison
object

The same statistics for the equal-length, inclusive period ending immediately before the requested start, together with the change between the two periods. Present only when compare=previous_period is requested. The change is already computed, so a percentage difference needs no second request.

Show child attributes
comparison.period
object
required

Equal-length window ending immediately before the requested start.

Show child attributes
comparison.delivery
object
required

SMS lifecycle counts and rates for a whole period or breakdown. Counts use the message send time, so a later delivery stays attributed to the bucket in which the message was sent. Rates are null when their denominator is zero.

Show child attributes
comparison.latency
object
required

Latency percentiles in milliseconds for the requested scope:

  • processing: From acceptance to carrier handoff.
  • delivery: From carrier handoff to delivery confirmation.
  • total: From acceptance to delivery confirmation.

Each family is omitted when no qualifying event contributes a measurement. Individual percentiles can also be null.

Show child attributes
comparison.delta
object
required

Changes from the previous period. A *_pct_change value is the signed relative change (current - previous) / previous and is null when the previous count is zero. A *_rate_pp value is the signed difference between rate fractions and is null when either rate is undefined.

Show child attributes
comparison.delta.accepted_pct_change
nullable number
required

Relative change in accepted messages (delivery.accepted) versus the previous period, as a signed fraction. Null when the previous period accepted none.

comparison.delta.sent_pct_change
nullable number
required

Relative change in sent messages (delivery.sent) versus the previous period, as a signed fraction. Null when the previous period had none.

comparison.delta.delivered_pct_change
nullable number
required

Relative change in delivered messages (delivery.delivered) versus the previous period, as a signed fraction. Null when the previous period delivered none.

comparison.delta.undelivered_pct_change
nullable number
required

Relative change in undelivered messages (delivery.undelivered) versus the previous period, as a signed fraction. Null when the previous period had none.

comparison.delta.failed_pct_change
nullable number
required

Relative change in failed messages (delivery.failed) versus the previous period, as a signed fraction. Null when the previous period had none.

comparison.delta.rejected_pct_change
nullable number
required

Relative change in rejected messages (delivery.rejected) versus the previous period, as a signed fraction. Null when the previous period had none.

comparison.delta.expired_pct_change
nullable number
required

Relative change in expired messages (delivery.expired) versus the previous period, as a signed fraction. Null when the previous period had none.

comparison.delta.delivery_rate_pp
nullable number
required

Signed difference between this period's and the previous period's delivery rate, both fractions in [0,1] (multiply by 100 for percentage points). Null when either period's delivery rate is undefined.

comparison.delta.failure_rate_pp
nullable number
required

Signed difference between the current and previous failure-rate fractions. Multiply by 100 for percentage points. The value can fall outside [-1, 1] because a message can contribute to more than one failure outcome and high-volume counts are approximate. Null when either rate is undefined.

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