LetterAgent
Mail physical letters by just asking your AI assistant.
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An online fax service converts your document to fax format on its own servers, then transmits it to the recipient's fax machine over its own phone lines. You upload or email a file, the service dials the number for you, and the other end receives a normal fax. No phone line, no machine, and no software to install on your end.
It stays at the fax provider's data center. A traditional fax call has two jobs: carrying the page images as audio signals, and negotiating the handshake (speed, resolution, page size) between the two machines. Online fax splits those jobs. Your part happens over the ordinary internet: you send a PDF, Word file, or image to the service's portal or email gateway. The provider's servers do the rest: they render your file into the same black-and-white page format a fax machine would produce, then place a real phone call to the destination fax number and push the pages through exactly as an old machine would. The recipient's fax machine cannot tell the difference, because at the wire level there isn't one.
First, the file is received and checked: page count verified, file format converted, color pages flattened to the monochrome palette that fax lines carry. Second, it is queued for dialing. Third, the service calls the recipient's number, performs the fax handshake, and transmits each page. Fourth, it produces a confirmation page or delivery report showing the number dialed, the pages sent, and the result. That confirmation is the part most people actually care about, and it is the closest thing faxing has to a read receipt. If the line is busy or the call fails, most services retry automatically a few times before reporting a failure.
| Traditional fax machine | Online fax service | |
|---|---|---|
| What you need | A fax machine and a phone line (or a VoIP adapter that handles fax) | A browser or email; the file you want to send |
| How pages travel | Paper is scanned, then sent as audio over the phone line | Your file is converted on the provider's servers, then sent over their phone lines |
| Receiving | Pages print out on the machine | Depends on the service: many deliver incoming faxes as PDF attachments; some services are send-only |
| Costs | Machine, paper, toner, phone line | Quoted per fax or on a plan; nothing to maintain |
It is one flavor of online fax. You send an email to a special address, often formatted as the recipient's fax number at the service's domain (something like 15555550123@service.example), with your document attached. The service turns the attachment into fax pages and dials. It works well for sending a fax straight from your phone without an app: take a photo of the document, attach it to an email, done. The catch is attachment formats. Most gateways accept PDF, DOC, and common image files, but a strange format or a huge file can fail silently, so PDF is the safest choice.
Usually not from the pages themselves. One detail can give it away: the sender-ID header line printed at the top of each page. Traditional machines print a header with the sender's name and phone number. Online services generate that same header line, often using the fax number assigned to your account or the email address you sent from. A header that reads like a webmail address is a quiet tell, but for most business purposes nobody cares how the pages arrived. They print, they read, and the content is identical.
Online fax cannot do everything a machine can. Some services cannot receive faxes at all, only send them. Color is not really a thing: fax transmission is monochrome, so your color document arrives in shades of gray. Double-sided pages and very large documents can hit page limits depending on the service. And like traditional fax, it is not encrypted end to end: it is a phone call, subject to interception in theory, though in practice far harder to intercept than most people assume. For routine business, government, and medical documents, that has been the accepted standard for decades.
With LetterAgent you send a fax by describing it to your AI assistant. The flow is a per-fax quote with the page count verified, you approve the exact total, you pay once through Stripe, and the fax is sent. LetterAgent covers US and Canadian fax numbers only, and it cannot receive inbound faxes. One important note: LetterAgent faxing is currently available in testing while activation is in progress, so it is described as available in testing. It is never guaranteed that a fax sends on a given day; if timing matters, ask your assistant about current status before you pay.
Ready to fax it? Fax with LetterAgent: describe it to your AI assistant, approve the exact quoted price, and it is sent.
LetterAgent is a working name. Prices include print, postage, and our service fee. US prices in USD, Canadian prices in CAD (Canadian prices exclude applicable sales tax, added at checkout). Currently in private testing.
Need help? Ask your assistant: it can check a job's status any time. If it ever can't handle something: hello@getletteragent.com