# Send a fax from a computer: four ways that work in 2026 > Browser upload, your mail client, fax software with a modem, or an API from a script. What to prepare, what each costs, and how to confirm the pages arrived. Page: https://faxforagents.com/blog/send-fax-from-computer/ Last changed: 2026-10-31 Browser upload, your mail client, fax software with a modem, or an API from a script. What to prepare, what each costs, and how to confirm the pages arrived. - Published Oct 31, 2026 - About 5 min read - By [Fax for Agents team](https://faxforagents.com/about/) You can send a fax from a computer in four ways. Use a browser service, a fax-to-email provider, modem software on a phone line, or an API from a script. - Use an online fax service in your browser when you want to upload a file yourself. - Use a fax-to-email provider when you want to send attachments from your usual mail client. - Use fax software with a modem when you already have an analog phone line and compatible equipment. - Use an API from a script when sending belongs inside a software workflow. ## Prepare the file Start with a PDF. Convert Word or Excel files to PDF for every route. Fax for Agents does not accept office formats. Flatten completed form fields into the page so their values appear in the fax image. Reopen the saved PDF and check the filled fields. Use letter or A4 pages, with black text on white. Remove password protection from the copy you intend to send. Prepare for monochrome fax at 204 by 98 dpi, or 204 by 196 dpi at fine resolution. A scan at 200 dpi in grayscale is enough for a readable text original. Higher scan resolution cannot repair faint writing or missing text. Inspect every page at a readable size. Check that tables stay inside the margins and signatures remain visible. Where the meaning depends on colour, add a text label, because the fax is black and white. ## Browser upload to an online fax service Create an account with an online fax service that supports browser uploads. Open its send page and upload your PDF. Enter the recipient's fax number in the format the provider requests. Check the country code against the number supplied by the recipient. Review the preview and page count before you send. Services charge by subscription or per page. Check the total, including any cover-page charge. Enable delivery emails if the service asks you to choose notifications. Press Send, then wait for the provider's delivery or failure email. Read the outcome and any reported page count. An upload confirmation says only that the service has your file. ## From your mail client Your fax-to-email provider must also support sending by email. Register your sending email address with the provider. Compose a message in your mail client and attach the PDF. Address it using the destination number and the provider's fax domain, following a pattern such as `number@provider.example`. The attachment becomes the fax. Providers set their own rules for using the subject or message body as a cover page. Check those rules before putting instructions in the message. Send the email and wait for the provider's result. Your mail client's Sent folder does not prove the fax reached its destination. The [email fax guide](https://faxforagents.com/blog/send-fax-from-email/) covers this route in detail. ## Fax software and a modem Use this route if you already have a fax modem and an analog phone line. The modem must support your operating system. Connect the modem to your computer and the line. Install its driver, then select it in your operating system's fax service or a third-party fax program. Open the PDF and use the program's send command or fax print destination. Enter the destination number and preview the pages. Start the call and leave the computer and modem connected until it finishes. This route works without internet access once the software is installed. It still needs an active phone line. You pay for the phone service and any call charges. Save or print the software's transmission report. ## From a script or an agent An API fits a script or an agent that sends documents as part of a larger task. Fax for Agents is a service for software and agents. Create a document, then quote it to a destination. The quote fixes the price and send details for ten minutes. Send that quote with an `Idempotency-Key`. This shell example uses Markdown, which the API renders to PDF. Replace `ffa_test_...` with your test key. Run each call after replacing its document or quote placeholder with the returned ID. ``` `FFA_KEY = 'ffa_test_...' FFA_API = 'https://api.faxforagents.com/v1' curl -sS " $FFA_API /documents" \ -H "Authorization: Bearer $FFA_KEY " -H 'Content-Type: application/json' \ -d '{"markdown":"Please confirm receipt by return fax."}' curl -sS " $FFA_API /fax-quotes" \ -H "Authorization: Bearer $FFA_KEY " -H 'Content-Type: application/json' \ -d '{"document_id":"doc_...","to":"+15550000001"}' curl -sS " $FFA_API /faxes" \ -H "Authorization: Bearer $FFA_KEY " -H 'Content-Type: application/json' \ -H 'Idempotency-Key: send-example-...' \ -d '{"quote_id":"quote_..."}'` ``` Set a unique `Idempotency-Key` for each new fax and reuse it on retries, so a timeout never sends the same pages twice. The answer is a job in state `queued`. Sends made with a test key go into the free sandbox, where every outcome can be rehearsed. A live API key needs a person's approval or a delegated policy that allows the send. The [quickstart](https://faxforagents.com/docs/quickstart/) explains setup. For a PDF upload and receipt retrieval, use the [send guide](https://faxforagents.com/docs/send-fax/). SDKs named `faxforagents` are available on PyPI and npm, with examples in the [SDK documentation](https://faxforagents.com/docs/sdks/). Sending to the United States and Canada costs $0.039 per page as of 2026-10-28. The minimum wallet top-up is $10 as of 2026-10-28. No subscription is needed. Cover pages count as pages. Failed sends are not charged. The [pricing table](https://faxforagents.com/pricing/) lists international rates. ## How to confirm it went through The transmission report or provider's delivery record is your evidence. Check the destination and confirmed page count against what you intended to send. Keep the report with your copy of the document. Fax for Agents records `delivered` only after it stores the provider's report confirming every page on the attempt. Read the receipt at `GET /v1/faxes/{id}/receipt`. It includes the provider reference and document hash. It also records the destination and amount captured. A `partial` result means only some pages were confirmed. An `unknown` result means there is no outcome yet. It is never retransmitted automatically. Check the status before starting another send. ## Questions ### Can I fax a Word document from my computer? Yes. Export the Word document as a PDF, then use any of the routes above. Open the exported file and check that every page appears as intended. Pay attention to tables near the page edge. Fax for Agents does not accept Word or Excel files, so PDF conversion is required before upload. ### Does my computer need a phone line to fax? Only the modem route needs a phone line connected to your equipment. If you send through a provider, it handles the phone connection. Your computer needs internet access for a browser service or an API. The same applies when you submit an email fax. ### Is faxing from a computer secure? HTTPS protects a browser or API upload to the provider. That protection ends where the fax call begins. Group 3 fax carries the page as plain image data over the public phone network. In ordinary use the receiving machine does not check who is calling. Check the number with the recipient, because a wrong number sends your document to a stranger. Fax for Agents is not a HIPAA service and does not sign business associate agreements. Protected health information must not be sent through it. ## On this site - [Send a fax](https://faxforagents.com/docs/send-fax/) - [SDKs](https://faxforagents.com/docs/sdks/) ## Related posts - [How to send a fax in 2026: machine, computer, email or API](https://faxforagents.com/blog/how-to-send-a-fax/) Every way to send a fax today, what each one needs and what it costs. How to know the pages arrived, and what to do when the line is busy. - [Send a fax from email: how email to fax works](https://faxforagents.com/blog/send-fax-from-email/) How an email to fax address is built, what the attachment must be and what the return mail proves. When an API fits software better than a mailbox.