InterFAX REST Fax API Reference


The InterFAX REST fax API is a commercial subscription-based service which enables transmission and reception of fax messages without the need to install any hardware or software. The original document to be transmitted may be of various formats, such as PDF, Microsoft Word, HTML, TXT etc. Received faxes are in TIF or PDF format.

As an extension to sending capabilities, the Interfax Fax REST API provides facilities for retrieving status information regarding fax messages sent through it.

It supports secure communications via HTTPS between the custom-programmed application and the Interfax server.

If you would like to use our advanced security REST API (compliant with PCI-DSS), please read our documentation here.

Available operations on resources

Operation & Resource Description
outbound faxes
POST /outbound/faxes

Submit a fax to a single destination number.

GET /outbound/faxes

Get a list of recent outbound faxes (which does not include batch faxes).

GET /outbound/faxes/completed

Get details for a subset of completed faxes from a submitted list. (Submitted id's which have not completed are ignored).

GET /outbound/faxes/{id}

Retrieves information regarding a previously-submitted fax, including its current status.

GET /outbound/faxes/{id}/image

Retrieve the fax image (TIFF file) of a submitted fax.

POST /outbound/faxes/{id}/cancel

Cancel a fax in progress.

POST /outbound/faxes/{id}/resend

Resend a previously-submitted fax, without needing to re-upload the original document.

POST /outbound/faxes/{id}/hide

Hide a fax from listing in queries (there is no way to unhide a fax).

outbound fax batches
POST /outbound/batches

Submit one or more documents for batch-faxing to multiple recipients.

GET /outbound/batches

Retrieve a list of outbound batches.

GET /outbound/batches/{id}

Retrieve information regarding a previously-submitted batch, including its completion statistics.

GET /outbound/batches/{id}/image

Retrieve the fax image (TIFF file) of a submitted batch.

GET /outbound/batches/{id}/resend

Resubmit a batch. Usually used to resubmit failed faxes only, to give them another try.

GET /outbound/batches/{id}/cancel

Cancel a batch in progress.

GET /outbound/batches/{id}/hide

Hide a batch from listing in queries. (There is no way to unhide a transaction). Hiding a batch also hides all its child faxes.

GET /outbound/addressbooks

Retrieve a list of distribution lists, to which batches may be sent.

outbound faxes and batches
GET /outbound/search

Search for outbound faxes.

GET /accounts/self/ppcards/balance

Determine the remaining faxing credits in your account.

outbound fax document uploads
POST /outbound/documents

Create a document upload session.

POST /outbound/documents/{id}

Upload a chunk to an existing document upload session.

GET /outbound/documents

Get a list of previous document uploads which are currently available.

GET /outbound/documents/{id}

Get the current status of a specific document upload.

DELETE /outbound/documents/{id}

Cancel a document upload and tear down the upload session, or delete a previous upload.

inbound faxes
GET /inbound/faxes

Retrieves a user's list of inbound faxes. (Sort order is always in descending ID).

GET /inbound/faxes/{id}

Retrieves a single fax's metadata (receive time, sender number, etc.).

GET /inbound/faxes/{id}/image

Retrieves a single fax's image.

GET /inbound/faxes/{id}/emails

Retrieve the list of email addresses to which a fax was forwarded.

POST /inbound/faxes/{id}/mark

Mark a transaction as read/unread.

POST /inbound/faxes/{id}/resend

Resend an inbound fax to a specific email address.

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