Trouble Sending Fax via EtherFAX API — Getting “400 Bad Request” Response

Hi everyone,

I’m trying to send a fax using the EtherFAX API, but I keep getting a 400 Bad Request response every time I submit my request. I’ve followed the documentation closely, set the correct headers (Content-Type: application/json), and included both the destination fax number and base64-encoded file data.

Here’s a snippet of my request body:

{
"Destination": "+15551234567",
"FileData": "",
"FileName": "testfax.pdf"
}

I’ve also confirmed that my API key and account ID are correct. Still, no luck — the same 400 error keeps coming back with a generic message.

Has anyone else experienced this issue? Could it be related to file size, encoding, or a missing parameter that’s not clearly documented? I’d appreciate any guidance or working examples of a successful API call.

Thanks in advance for any help! ragdoll hit