Send up to 100 messages

POST/v1/email/batch

TypeScript sendora.email.sendBatch(messages)

Python sendora.email.send_batch(messages)

Key sk_… a server key

Accepts an array of messages and answers one result per message, in order: accepted with its id, or refused with the same error the single send would give. The Idempotency-Key is required. A retry under the same key sends nothing twice: every item accepted before is answered again with replayed set, and only the items that failed are attempted again.

Parameters

• idempotency-keyin headerstringrequired

  Any text of 1 to 255 printable characters that identifies this batch; the same key with a different item is refused for that item.

Request body

• fromone of 2required

  The sender. Its domain must be a verified sending domain of the server.

  1. string (email)
  2. • emailstring (email)required
     • namestring (at least 1, at most 200 characters) or null

       A display name of up to 200 characters.

• streamIdstring (uuid)

  The stream of this server the message goes on; the default transactional stream when absent.

• toarray of one of 2, at least 1required

  Recipients; at most 50 across to, cc and bcc.

  1. string (email)
  2. • emailstring (email)required
     • namestring (at least 1, at most 200 characters) or null

       A display name of up to 200 characters.

• ccarray of one of 2

  Copied recipients, shown in the message.

  1. string (email)
  2. • emailstring (email)required
     • namestring (at least 1, at most 200 characters) or null

       A display name of up to 200 characters.

• bccarray of one of 2

  Blind-copied recipients.

  1. string (email)
  2. • emailstring (email)required
     • namestring (at least 1, at most 200 characters) or null

       A display name of up to 200 characters.

• subjectstring (at least 1, at most 998 characters)required

  The subject line.

• textstring (at least 1 character)

  The plain-text part. At least one of text and html is required.

• htmlstring (at least 1 character)

  The HTML part.

• headersmap of string to stringdefault {}

  Custom headers by name, at most 20. Sendora writes these itself, so a message may not set them: From, Sender, To, Cc, Bcc, Subject, Date, Message-ID, MIME-Version, Return-Path, Received, Delivered-To, DKIM-Signature, DomainKey-Signature, Authentication-Results, Received-SPF, and any name that starts with Content-, Resent-, ARC- or X-Kumo.

• attachmentsarray of object, at most 20

  At most 20. A message with its attachments encoded may be at most 10 MB.

  • namestringrequired
  • contentstring (base64)required
  • contentTypestring
  • contentIdstring or null
• tagstring or null

  A label of up to 100 characters, returned with the message and its events.

• metadatamap of string to stringdefault {}

  Up to 20 key-value pairs of your own, returned with the message and its events.

[
  {
    "from": {
      "email": "no-reply@example.se",
      "name": "Example AB"
    },
    "to": [
      "anna@example.com"
    ],
    "subject": "Your invoice for September",
    "text": "Hi Anna, your invoice is attached.",
    "attachments": [
      {
        "name": "invoice.pdf",
        "content": "JVBERi0xLjcK",
        "contentType": "application/pdf"
      }
    ],
    "tag": "invoice",
    "metadata": {
      "invoiceId": "2026-0912"
    }
  }
]

Responses

{
  "results": [
    {
      "index": 0,
      "messageId": "5f432ffd-c005-499b-aa3a-5b8a088ea20e",
      "status": "accepted",
      "submittedAt": "2026-09-15T12:00:00.000Z",
      "test": false,
      "replayed": false
    }
  ]
}

Errors

Every error answers error, the code, and message, a sentence for a person. A code that adds fields is shown in full below the table.

• Retry-Afterheader on 503integer

  Seconds to wait before trying again.

{
  "error": "invalid_request",
  "message": "The request is invalid: to.0: Invalid email address",
  "issues": [
    {
      "path": "to.0",
      "message": "Invalid email address"
    }
  ]
}