--- title: "Get statistics by recipient domain" canonical: "https://bird.com/docs/api/reference/get-email-stats-by-recipient-domain" --- # Get statistics by recipient domain `GET /v1/email/stats/recipient-domains` Returns delivery and engagement counts for the requested period, grouped by recipient mailbox domain: the part of each recipient address after the `@`, for example `gmail.com`, `yahoo.com`, or `outlook.com`. This is the finest-grained deliverability view. Where the mailbox-provider breakdown groups recipients into provider buckets such as `gmail` or `microsoft`, this keys on the exact destination domain. Use it to spot a delivery-rate dip or a complaint spike at a specific domain. Rows are ranked by the `sort` metric, `processed` by default, and paginated with the requested `limit` (50 by default, 200 at most). Rows are computed against event time rather than send time, so engagement received during the period counts even for messages that were sent earlier. The window can span at most 365 days. Ask for more and you get a `422`. ## Code samples **TypeScript** ```ts const { data } = await bird.email.stats.byRecipientDomain({ from: "2026-05-01", to: "2026-05-31", sort: "bounce_rate", limit: 25, }); for (const row of data) console.log(row.recipient_domain, row.delivery.bounce_rate); ``` Examples: [TypeScript](/docs/api/reference/get-email-stats-by-recipient-domain.ts.md) · [Python](/docs/api/reference/get-email-stats-by-recipient-domain.py.md) · [Go](/docs/api/reference/get-email-stats-by-recipient-domain.go.md) · [PHP](/docs/api/reference/get-email-stats-by-recipient-domain.php.md) · [CLI](/docs/api/reference/get-email-stats-by-recipient-domain.cli.md) · [MCP](/docs/api/reference/get-email-stats-by-recipient-domain.mcp.md) · [cURL](/docs/api/reference/get-email-stats-by-recipient-domain.curl.md) ## Example response `200` ```json { "period": { "from": "2026-05-01", "to": "2026-05-25", "data_as_of": "2026-05-25T14:03:10Z" }, "data": [ { "recipient_domain": "gmail.com", "delivery": { "accepted": 14820, "processed": 14810, "delivered": 14720, "bounced": 90, "bounces": { "hard": 12410, "soft": 14290, "admin": 410, "block": 920, "undetermined": 80, "hard_rate": 0.454, "soft_rate": 0.523, "admin_rate": 0.015, "block_rate": 0.0337, "undetermined_rate": 0.0029 }, "complained": 3, "deferred": 14, "rejected": 10, "oob_bounces": 2, "effective_delivered": 14718, "all_bounces": 92, "oob_rate": 0.00014, "delivery_rate": 0.9939, "bounce_rate": 0.0061, "complaint_rate": 0.0002 }, "engagement": { "opens": 5420, "opens_non_prefetched": 3210, "unique_opens": 3640, "unique_opens_non_prefetched": 2480, "clicks": 924, "unique_clicks": 621, "unsubscribes": 12, "open_rate": 0.1683, "click_rate": 0.0422, "unsubscribe_rate": 0.0009 }, "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 } }, "trend": [ { "bucket": "2026-05-12" } ] } ], "total": 412, "next_cursor": "eyJ2IjoxLCJzIjoiXCIyMDI2LTA1LTI1VDE0OjAzOjEwWlwiIiwiaSI6IjAxOTJmM2IxLTRjN2UtN2EyYi05ZDYxLThmM2E1YzJlN2I0MCJ9", "prev_cursor": null, "refresh_cursor": "eyJ2IjoxLCJzIjoiXCIyMDI2LTA1LTI1VDE2OjQyOjAxWlwiIiwiaSI6IjAxOTJmM2IxLTllMDQtN2NkMy1iODE3LTJhNmY0ZDFjOGUwOSJ9" } ``` ## Query parameters - `starting_after` (string): Cursor from the `next_cursor` field of a previous list response. Returns items immediately after the cursor position in the current sort order. - `ending_before` (string): Cursor from the `prev_cursor` or `refresh_cursor` field of a previous list response. Returns items immediately before the cursor position in the current sort order. `prev_cursor` returns the preceding page. `refresh_cursor` anchors at the first row of that response, which on a newest-first sort is how to fetch the items that have appeared since. - `from` (string): Start date (inclusive) in `YYYY-MM-DD`, interpreted as a calendar day in `timezone` (a UTC day when `timezone` is omitted). It defaults to 30 days before `to` when you leave it out. When `include_trend=true` and `trend_grain=hourly`, that default tightens to 29 days before `to` instead, so the defaulted window still fits inside the 720-hour trend cap. - `to` (string): End date (inclusive) in `YYYY-MM-DD`, interpreted as a calendar day in `timezone` (a UTC day when `timezone` is omitted). Defaults to today in that timezone when omitted. Window may not exceed 365 days. - `timezone` (string): 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. - `category` (string): Not supported on breakdown endpoints. Supplying it returns `422`. To compare categories, use `GET /v1/email/stats/categories`. The summary, daily, and hourly statistics accept `category` as a filter. - `sort` (string) Metric to rank rows by, applied descending. Any count or rate in the response can be used. A row whose rate is undefined because its denominator is zero sorts last. It defaults to `processed`. Possible values: `processed`, `delivered`, `bounced`, `complained`, `deferred`, `rejected`, `oob_bounces`, `bounces.hard`, `bounces.soft`, `bounces.admin`, `bounces.block`, `bounces.undetermined`, `opens`, `opens_non_prefetched`, `unique_opens`, `unique_opens_non_prefetched`, `clicks`, `unique_clicks`, `unsubscribes`, `delivery_rate`, `bounce_rate`, `complaint_rate`, `open_rate`, `click_rate`, `unsubscribe_rate`, `bounces.hard_rate`, `bounces.soft_rate`, `bounces.admin_rate`, `bounces.block_rate`, `bounces.undetermined_rate` - `limit` (integer): Maximum number of recipient-domain rows to return, ranked by the `sort` field descending. - `include_trend` (boolean): When true, each row also gets a `trend` array: a short per-bucket series showing that recipient domain's delivery and engagement rates over the window. This only works when `limit` is 50 or fewer and the window is at most 90 days for `trend_grain=daily` or 720 hours for `trend_grain=hourly`. Ask for more and you get a `422`. When you leave `from` out and use `trend_grain=hourly`, the default window tightens to 29 days before `to` (720 hours total), so a request built entirely from defaults always fits inside the cap. - `trend_grain` (string) Bucket grain for the `trend` series. Has no effect unless `include_trend=true`. Possible values: `daily`, `hourly` ## Response body - `period` (object, required): The date range the response covers (echoed back from the request), plus `data_as_of`, the freshness boundary the data is current to. - `period.from` (string, required): Inclusive start date the response covers (YYYY-MM-DD). - `period.to` (string, required): Inclusive end date the response covers (YYYY-MM-DD). - `period.data_as_of` (nullable string): The instant the statistics in this response are current to: events recorded up to roughly this time are reflected, while more recent events may not be yet. Statistics are served from a rolling aggregation that refreshes every few seconds, so a response reflects data from up to a few seconds ago. Use this field to label data freshness (for example "as of 14:03") rather than assuming the numbers are to-the-second. Null when the freshness boundary is not being reported. - `data` (array of object, required): Recipient-domain breakdown rows, ranked by the `sort` metric (default `processed`) descending. Empty when no eligible activity occurred in the period. - `data.recipient_domain` (string, required): The recipient mailbox domain this row aggregates (the part of the recipient address after the `@`), normalized to lowercase. - `data.delivery` (object, required) - `data.delivery.accepted` (integer): Distinct recipients accepted for delivery after suppression filtering. Reported on time buckets and the period summary. Breakdown rows leave it out, because their rollups do not have it. - `data.delivery.processed` (integer, required): Distinct recipients whose message was processed and handed off for delivery. - `data.delivery.delivered` (integer, required): Distinct recipients whose message the receiving mail server accepted. - `data.delivery.bounced` (integer, required): Distinct recipients whose delivery failed. This is approximately the sum of the five `bounces.*` sub-counts (hard, soft, admin, block, undetermined). The two totals are worked out independently, so they can differ slightly. - `data.delivery.bounces` (object, required) - `data.delivery.bounces.hard` (integer, required): Distinct recipients with a permanent delivery failure (invalid address or non-existent domain). - `data.delivery.bounces.soft` (integer, required): Distinct recipients with a transient delivery failure (mailbox full or server temporarily unavailable). - `data.delivery.bounces.admin` (integer, required): Distinct recipients refused by a policy at the receiving end, such as relaying denied or a blocklisted domain. - `data.delivery.bounces.block` (integer, required): Distinct recipients bounced because the receiving mail server blocked the sending IP for reputation reasons. - `data.delivery.bounces.undetermined` (integer, required): Distinct recipients bounced where the receiving server's response did not allow precise classification. - `data.delivery.bounces.hard_rate` (nullable number, required): Fraction of bounced recipients that hard bounced, computed as `hard / bounced`. Null when `bounced` is zero. - `data.delivery.bounces.soft_rate` (nullable number, required): Fraction of bounced recipients that soft bounced, computed as `soft / bounced`. Null when `bounced` is zero. - `data.delivery.bounces.admin_rate` (nullable number, required): Fraction of bounced recipients that admin bounced, computed as `admin / bounced`. Null when `bounced` is zero. - `data.delivery.bounces.block_rate` (nullable number, required): Fraction of bounced recipients that block bounced, computed as `block / bounced`. Null when `bounced` is zero. - `data.delivery.bounces.undetermined_rate` (nullable number, required): Fraction of bounced recipients with undetermined classification, computed as `undetermined / bounced`. Null when `bounced` is zero. - `data.delivery.complained` (integer, required): Distinct recipients who reported the message as spam via a feedback loop. - `data.delivery.deferred` (integer, required): Distinct recipients whose delivery the receiving server temporarily delayed and is still being retried. - `data.delivery.rejected` (integer, required): Distinct recipients rejected before any delivery attempt. Includes recipients on the workspace suppression list, transmissions that could not be completed, message-generation failures, and recipients refused by sending policy. The per-recipient `rejection_reason` field on `GET /v1/email/messages/{message_id}/recipients` surfaces the specific cause. - `data.delivery.oob_bounces` (integer, required): Out-of-band bounce events: distinct failure notifications received after the receiving server had initially confirmed delivery. The count represents deduplicated events rather than unique recipients. - `data.delivery.effective_delivered` (integer, required): Recipients who remain delivered after all bounce signals resolve, computed as `delivered - oob_bounces`. Use this as the base for engagement-rate denominators. Clamped to 0 when `oob_bounces` exceeds `delivered`. - `data.delivery.all_bounces` (integer, required): Total recipients in this scope who did not receive the message, computed as `bounced + oob_bounces`. - `data.delivery.oob_rate` (nullable number, required): Share of this scope's delivery attempts that resulted in an out-of-band bounce, computed as `oob_bounces / (delivered + bounced)`. Null when there were no attempts. - `data.delivery.delivery_rate` (nullable number, required): Share of this scope's delivery attempts that remained delivered after all bounce signals, computed as `effective_delivered / (delivered + bounced)`. Null when there were no attempts. - `data.delivery.bounce_rate` (nullable number, required): Share of this scope's delivery attempts that ultimately failed (inband or out-of-band), computed as `all_bounces / (delivered + bounced)`. Because `oob_bounces` counts events rather than recipients, `all_bounces` can exceed the attempt count. The rate is clamped to 1. Null when there were no attempts. - `data.delivery.complaint_rate` (nullable number, required): Spam complaints in this scope relative to effectively delivered recipients, computed as `complained / effective_delivered`. Complaints are attributed by event time, so a scope can record more of them than it effectively delivered, pushing the rate above 1. Null when `effective_delivered` is zero. - `data.engagement` (object, required) - `data.engagement.opens` (integer, required): Distinct open events, counting repeat opens from the same recipient and opens auto-fetched by inbox privacy features (such as Apple Mail Privacy Protection and the Gmail image proxy). - `data.engagement.opens_non_prefetched` (integer, required): Distinct open events excluding those auto-fetched by inbox privacy features. Same event-counting semantics as `opens` (repeat opens from the same recipient count separately), with prefetched opens removed. - `data.engagement.unique_opens` (integer, required): Distinct recipients who opened at least once, including opens auto-fetched by inbox privacy features. - `data.engagement.unique_opens_non_prefetched` (integer, required): Distinct recipients who opened at least once, excluding opens auto-fetched by inbox privacy features. This is the numerator used for open rate, so iOS-heavy audiences (Apple Mail Privacy Protection and similar) do not inflate it. - `data.engagement.clicks` (integer, required): Distinct click events, counting repeat clicks from the same recipient. - `data.engagement.unique_clicks` (integer, required): Distinct recipients who clicked at least once. - `data.engagement.unsubscribes` (integer, required): Distinct unsubscribe events, recorded via the list-unsubscribe header or the footer link. - `data.engagement.open_rate` (nullable number, required): Distinct non-prefetched openers relative to effectively delivered recipients in the same scope, computed as `unique_opens_non_prefetched / delivery.effective_delivered`; on rows without an `effective_delivered` field (the mailbox-provider breakdowns) the denominator equals `delivery.delivered`. The numerator excludes opens auto-fetched by inbox privacy features. Opens are attributed by event time, so engagement earned by earlier deliveries can push the rate above 1. Null when the denominator is zero. - `data.engagement.click_rate` (nullable number, required): Distinct clickers relative to effectively delivered recipients in the same scope, computed as `unique_clicks / delivery.effective_delivered` (`delivery.delivered` on rows without an `effective_delivered` field). Clicks are attributed by event time, so engagement earned by earlier deliveries can push the rate above 1. Null when the denominator is zero. - `data.engagement.unsubscribe_rate` (nullable number, required): Unsubscribe events relative to effectively delivered recipients in the same scope, computed as `unsubscribes / delivery.effective_delivered` (`delivery.delivered` on rows without an `effective_delivered` field). Unsubscribes are attributed by event time, so the rate can exceed 1. Null when the denominator is zero. - `data.latency` (object, required) - `data.latency.processing` (object): Approximate p50, p95, and p99 latency percentiles in milliseconds for one latency family over the bucket. All three are null when no qualifying event contributed a measurement. - `data.latency.processing.p50_ms` (nullable integer, required): Median (50th percentile) latency in milliseconds. Null when no qualifying event contributed a measurement. - `data.latency.processing.p95_ms` (nullable integer, required): 95th percentile latency in milliseconds. Null when no qualifying event contributed a measurement. - `data.latency.processing.p99_ms` (nullable integer, required): 99th percentile latency in milliseconds. Null when no qualifying event contributed a measurement. - `data.latency.delivery` (object): Approximate p50, p95, and p99 latency percentiles in milliseconds for one latency family over the bucket. All three are null when no qualifying event contributed a measurement. - `data.latency.delivery.p50_ms` (nullable integer, required): Median (50th percentile) latency in milliseconds. Null when no qualifying event contributed a measurement. - `data.latency.delivery.p95_ms` (nullable integer, required): 95th percentile latency in milliseconds. Null when no qualifying event contributed a measurement. - `data.latency.delivery.p99_ms` (nullable integer, required): 99th percentile latency in milliseconds. Null when no qualifying event contributed a measurement. - `data.latency.total` (object): Approximate p50, p95, and p99 latency percentiles in milliseconds for one latency family over the bucket. All three are null when no qualifying event contributed a measurement. - `data.latency.total.p50_ms` (nullable integer, required): Median (50th percentile) latency in milliseconds. Null when no qualifying event contributed a measurement. - `data.latency.total.p95_ms` (nullable integer, required): 95th percentile latency in milliseconds. Null when no qualifying event contributed a measurement. - `data.latency.total.p99_ms` (nullable integer, required): 99th percentile latency in milliseconds. Null when no qualifying event contributed a measurement. - `data.trend` (array of object): Per-bucket rate series for this recipient domain over the window. Present only when `include_trend=true`. - `data.trend.bucket` (string, required): The day (YYYY-MM-DD) or hour (ISO 8601, on the hour) this point covers, matching the requested `trend_grain`. - `data.trend.delivered` (integer, required): Delivered recipients in this bucket. - `data.trend.bounced` (integer, required): Bounced recipients in this bucket. - `data.trend.delivery_rate` (nullable number, required): Delivery rate for this bucket, as a fraction. Null when nothing was delivered or bounced. - `data.trend.bounce_rate` (nullable number, required): Bounce rate for this bucket, as a fraction. Null when nothing was delivered or bounced. - `data.trend.complaint_rate` (nullable number, required): Complaint rate for this bucket, as a fraction. Event-time attribution can push it above 1 when complaints outrun the bucket's deliveries. Null when nothing was delivered in the bucket. On a sending-IP row complaints are not attributed to the IP, so this reads 0 in buckets that had deliveries and null in buckets that had none. - `data.trend.open_rate` (nullable number, required): Open rate for this bucket, as a fraction. Event-time attribution can push it above 1 when opens outrun the bucket's deliveries. Null when nothing was delivered in the bucket. On a sending-IP row engagement is not attributed to the IP, so this reads 0 in buckets that had deliveries and null in buckets that had none. - `data.trend.click_rate` (nullable number, required): Click rate for this bucket, as a fraction. Event-time attribution can push it above 1 when clicks outrun the bucket's deliveries. Null when nothing was delivered in the bucket. On a sending-IP row engagement is not attributed to the IP, so this reads 0 in buckets that had deliveries and null in buckets that had none. - `total` (integer, required): Total number of distinct recipient domains with activity in the period, regardless of `limit`. Pass `next_cursor` as `starting_after` to request the next page. - `next_cursor` (nullable string, required): Cursor for the next page. Pass back as `starting_after` to advance forward. `null` when no next page exists. - `prev_cursor` (nullable string, required): Cursor for the previous page. Pass back as `ending_before` to step backward. `null` when no previous page exists. - `refresh_cursor` (nullable string, required): Refresh anchor, the first row of this response. Pass back as `ending_before` to fetch what precedes it in the current sort order. On a newest-first sort those are the items that have appeared since; on any other sort they are the items that sort earlier, so refreshing such a list means re-fetching it instead. Non-`null` whenever `data` is non-empty; `null` only on an empty page. Distinct from `prev_cursor`. ## Related resources - [What is click-through rate for email and SMS?](/explained/engagement/what-is-click-through-rate) (answer) - [Email analytics](/email-api/features/analytics) (product) - [Email metrics](/docs/guides/email/tracking-and-metrics) (docs) [Get an implementation brief](/learn/workspace?topic=email-metrics)