# Preview subscriber deliveries — API reference > Previews e-mail and webhook deliveries for a status-page update without queueing messages or consuming page limits. Source: https://upfour.io/docs/api/status-pages/preview-subscriber-deliveries [Developers](https://upfour.io/docs/api.md)/[Status pages](https://upfour.io/docs/api/status-pages.md) Previews e-mail and webhook deliveries for a status-page update without queueing messages or consuming page limits. GET https://app.upfour.io/v1/status-pages/{pageID}/mail-preview scope status_page.read stable returns 200 ## Parameters | Field | Type | Description | | --- | --- | --- | | `pageID` required | uuid | path parameter | | `kind` required | string one of`start` `interim` `resolution` | query parameter · The entry about to be published: `start` (first entry of a new incident or maintenance, also publishing a draft), `interim` (an update in between) or `resolution` (resolved, completed, cancelled). | | `update_id` optional | uuid | query parameter · The thread the entry belongs to. Its type and components win over `type` and `resource_ids`. Without it the thread is new and nobody has been mailed about it yet. | | `type` optional | string one of`incident` `maintenance` `report` | query parameter · Type of a thread that does not exist yet (default `incident`). | | `resource_ids` optional | string | query parameter · Comma-separated affected components of a thread that does not exist yet; empty means all subscribers. | ## Returns A successful request returns `200` with application/json. Response fields 1 top-level fields | Field | Type | Description | | --- | --- | --- | | `data` | MailPreview | | | MailPreview · 28 fields FieldTypeDescription `billing_paused` boolean `email` MailPreviewEmail MailPreviewEmail · 11 fields FieldTypeDescription `folded` integer `groups` MailPreviewGroup[] · nullable Each item · 5 fields FieldTypeDescription `count` integer `earliest` string (date-time) · nullable `latest` string (date-time) · nullable `outcome` string one of`folded` `not_sent` `reason` string `immediate` integer `next_mail_at` string (date-time) · nullable `not_sent` integer `recipients` integer `generated_at` string (date-time) `kind` string one of`start` `interim` `resolution` `limits` MailPreviewLimits MailPreviewLimits · 5 fields FieldTypeDescription `brake_mails` integer `brake_window_seconds` integer `interim_window_seconds` integer `page_burst` integer `page_entries_per_hour` integer `quota_level` string one of`ok` `warn` `bundle` `hold` `stop` `update_id` uuid · nullable null when the preview is for a thread that does not exist yet. `update_type` string one of`incident` `maintenance` `report` `webhook` MailPreviewWebhook MailPreviewWebhook · 3 fields FieldTypeDescription `immediate` integer `not_sent` integer `recipients` integer | | | ## Errors Only the errors this operation can return. Every error uses the [same envelope](https://upfour.io/docs/api/responses.md). | Status | Code | Meaning | | --- | --- | --- | | 400 | [bad_request](https://upfour.io/docs/api/errors#code-bad_request) | The request is malformed or fails validation. | | 404 | [not_found](https://upfour.io/docs/api/errors#code-not_found) | The requested resource does not exist or is outside the caller's scope. | Every call can also return `unauthorized` (401), `rate_limit_exceeded` (429) or `internal_error` (500 / 502). See [Responses and errors](https://upfour.io/docs/api/responses.md). [PreviousDuplicate a status page](https://upfour.io/docs/api/status-pages/duplicate-a-status-page.md) [NextList report updates](https://upfour.io/docs/api/status-pages/list-report-updates.md) ## Request ### cURL ```bash curl -s "https://app.upfour.io/v1/status-pages/00000000-0000-4000-8000-000000000001/mail-preview?kind=start" \ -H "Authorization: Bearer $UP4_API_KEY" ``` ### JavaScript ```javascript const res = await fetch("https://app.upfour.io/v1/status-pages/00000000-0000-4000-8000-000000000001/mail-preview?kind=start", { headers: { Authorization: `Bearer ${process.env.UP4_API_KEY}`, }, }); console.log(res.status, await res.json()); ``` ### Python ```python import os import requests res = requests.get( "https://app.upfour.io/v1/status-pages/00000000-0000-4000-8000-000000000001/mail-preview?kind=start", headers={"Authorization": f"Bearer {os.environ['UP4_API_KEY']}"}, ) print(res.status_code, res.json()) ``` ### Go ```go package main import ( "fmt" "io" "net/http" "os" ) func main() { req, _ := http.NewRequest("GET", "https://app.upfour.io/v1/status-pages/00000000-0000-4000-8000-000000000001/mail-preview?kind=start", nil) req.Header.Set("Authorization", "Bearer "+os.Getenv("UP4_API_KEY")) res, err := http.DefaultClient.Do(req) if err != nil { panic(err) } defer res.Body.Close() out, _ := io.ReadAll(res.Body) fmt.Println(res.StatusCode, string(out)) } ``` ### PHP ```php true, CURLOPT_HTTPHEADER => [ "Authorization: Bearer " . getenv("UP4_API_KEY"), ], ]); $response = curl_exec($ch); echo curl_getinfo($ch, CURLINFO_RESPONSE_CODE), " ", $response, "\n"; curl_close($ch); ``` ## Response ### 200 ```json { "data": { "billing_paused": false, "email": { "folded": 0, "groups": [], "immediate": 0, "next_mail_at": null, "not_sent": 0, "recipients": 0 }, "generated_at": "2026-10-27T09:00:00Z", "kind": "start", "limits": { "brake_mails": 20, "brake_window_seconds": 86400, "interim_window_seconds": 1800, "page_burst": 5, "page_entries_per_hour": 10 }, "quota_level": "ok", "update_id": null, "update_type": "incident", "webhook": { "immediate": 0, "not_sent": 0, "recipients": 0 } } } ``` ### 400 ```json { "error": { "code": "bad_request", "message": "The request is malformed or fails validation.", "request_id": "req_…" } } ``` ### 404 ```json { "error": { "code": "not_found", "message": "The requested resource does not exist or is outside the caller's scope.", "request_id": "req_…" } } ```