Dropbox Sign Developer Documentation

curl -X POST 'https://api.hellosign.com/v3/fax/send' \
  -u 'YOUR_API_KEY:' \
  -F 'files[0]=@mutual-NDA-example.pdf' \
  -F 'test_mode=1' \
  -F 'recipient=16690000001' \
  -F 'sender=16690000000' \
  -F 'cover_page_to=Jill Fax' \
  -F 'cover_page_message=I sent you a fax!' \
  -F 'cover_page_from=Faxer Faxerson' \
  -F 'title=This is what the fax is about!'

{
  "fax": {
    "fax_id": "c2e9691c85d9d6fa6ae773842e3680b2b8650f1d",
    "title": "example title",
    "original_title": "example original title",
    "metadata": [],
    "created_at": 1726774555,
    "sender": "me@dropboxsign.com",
    "files_url": "https://api.hellosign.com/v3/fax/files/2b388914e3ae3b738bd4e2ee2850c677e6dc53d2",
    "transmissions": [
      {
        "recipient": "recipient@dropboxsign.com",
        "status_code": "success",
        "sent_at": 1723231831,
        "sender": "me@dropboxsign.com"
      }
    ],
    "subject": "example subject",
    "message": "example message"
  }
}

Creates and sends a new Fax with the submitted file(s)

Authentication

AuthorizationBasic

Your API key can be used to make calls to the Dropbox Sign API. See Authentication for more information. ✅ Supported by Try it console (calls sent in test_mode only).

AuthorizationBearer

You can use an Access Token issued through an OAuth flow to send calls to the Dropbox Sign API from your app. The access scopes required by this endpoint are listed in the gray box above. See Authentication for more information. ❌ Not supported by Try it console.

You can use an Access Token issued through an OAuth flow to send calls to the Dropbox Sign API from your app. The access scopes required by this endpoint are listed in the gray box above. See [Authentication](/api/reference/authentication) for more information. ❌ **Not supported** by Try it console.

Request

This endpoint expects an object.

recipientstringRequired

Recipient of the fax Can be a phone number in E.164 format or email address

senderstringOptional

Fax Send From Sender (used only with fax number)

fileslist of stringsOptional

Use files[] to indicate the uploaded file(s) to fax

This endpoint requires either files or file_urls[], but not both.

file_urlslist of stringsOptional

Use file_urls[] to have Dropbox Fax download the file(s) to fax

This endpoint requires either files or file_urls[], but not both.

test_modebooleanOptionalDefaults to false

API Test Mode Setting

cover_page_tostringOptional

Fax cover page recipient information

cover_page_fromstringOptional

Fax cover page sender information

cover_page_messagestringOptional

Fax Cover Page Message

titlestringOptional

Fax Title

Response headers

X-RateLimit-Limitinteger

The maximum number of requests per hour that you can make.

X-RateLimit-Remaininginteger

The number of requests remaining in the current rate limit window.

X-Ratelimit-Resetinteger

The Unix time at which the rate limit will reset to its maximum.

Response

successful operation

faxobject

warningslist of objects

A list of warnings.

Errors

4XX

Client Request Error