How to Fax From a Computer: Windows, Mac & Online (2026)

By Alexey Spasskiy · Published January 3, 2025 · Updated August 13, 2026 · 14 min read

Quick Answer: To fax from a computer, open an online fax service in your browser, upload your document, type the recipient's fax number, and click Send — the service converts the file and transmits it over the internet. No fax machine, modem, or phone line is required. Windows and Mac users can also install a desktop fax app.

Faxing survived because hospitals, courts, pharmacies, insurers, and government offices standardized on it decades ago and never stopped. Sooner or later you end up staring at a 10-digit fax number with no fax machine in sight — just the computer in front of you.

So, can you fax from a computer? Yes — six different ways, and five of them need no hardware at all. We have sent test faxes through every route below, on Windows, macOS, and a Chromebook, so what follows is the real steps and the real requirements rather than the feature list on a pricing page. Timings, costs, and store details were last verified on 13 August 2026.

Every Way to Fax From a Computer, Compared

Six routes exist. Only the first three are realistic for most people in 2026.

The split is simple. If a method sends your document over the internet, all you need is an account. If it sends over the telephone network, you need a modem and an analog line — and analog lines are exactly what most homes and offices no longer have.

Method 1: Fax From a Computer in a Web Browser (Any Operating System)

This is what most people mean when they ask how to send a fax from a computer, and it is where to start. Open a web page, upload a file, enter a number, send. Nothing is installed, and it behaves identically on a Windows desktop, a MacBook, a Chromebook, or a Linux workstation.

What file types can you send?

Fax is a black-and-white raster format, so everything is converted first. You can upload:

• PDF — the safest choice, because nothing about the layout can shift
• Word, Excel, PowerPoint, OpenDocument — converted automatically
• Images — PNG, JPG, BMP, GIF, WebP, including phone photos of paper
• Plain text, RTF, CSV, HTML — rendered onto pages for you

Color is flattened to black and white, so a pale highlight can disappear and a mid-gray signature can turn muddy. Check the preview before sending a signature or a stamp.

Method 2: mFax for Windows — the Native Desktop App

If the computer is a Windows PC, you can skip the browser entirely. mFax for Windows is a native desktop app on the Microsoft Store: free to install, about 46 MB, published by Octagon Lab. It needs Windows 10 version 17763.0 or later, and it ships both x64 and ARM64 builds — so it runs natively on Snapdragon-based Copilot+ PCs, which is exactly where the built-in Windows Fax and Scan is not available at all.

It sends over the internet, like the web version. No modem, no landline, no printer driver.

How to send a fax from the Windows app

1. Install it from the Microsoft Store and sign in with your email address — or start as a guest. Sign-in is email-only, so there is no password to create.
2. Add the document. Drag it in from File Explorer, paste an image from the clipboard, or browse for it. PDF, Word, Excel, PowerPoint, OpenDocument, RTF, TXT, CSV, HTML, and common image formats are all converted to fax-ready pages.
3. Fix it before it goes. Reorder, rotate, duplicate, delete, or extract pages; draw in seven ink colors; add a caption; sign with a mouse, trackpad, or pen and place the signature. Full undo and redo.
4. Generate a cover page with your name, contact details, and a message, marked Urgent, Confidential, For Review, Please Reply, or Please Comment.
5. Enter the number — pick the country from the picker and type the digits; the app formats them as you go.
6. Send. You get live progress with a time estimate, then a delivery receipt you can download as a shareable PDF. Failures are explained in plain language — busy line, no answer, no fax signal, number out of service — instead of an error code.

You can also claim your own fax number inside the app, and teams can create an organization and share one workspace, number, and history.

Limits worth knowing: up to 60 pages per fax and 20 MB per file. An internet connection and an mFax account are required — there is no offline mode. The app is free to install; sending faxes and a dedicated fax number need a subscription — the first 7 days are free, then $7.99/month.

Full walkthrough: mFax for Windows. For the Windows-specific version of this whole guide, see how to fax from a PC.

Method 3: Windows Fax and Scan (Free, but It Needs a Modem and a Landline)

Windows Fax and Scan has shipped with Windows since Vista and is still in Windows 10 and Windows 11. It is genuinely free — and it traps more people than any other method, because the software being installed says nothing about whether you can use it.

It sends over the telephone network, not the internet. That means two things your PC almost certainly lacks:

• A fax modem — internal card or USB dongle. Laptops stopped shipping with built-in modems well over a decade ago; a USB unit runs $20–$50.
• An analog phone line — a real copper POTS line. VoIP lines from a cable or fibre provider frequently mangle fax tones, and a mobile hotspot cannot carry a fax call at all.

There is a third catch: Windows Fax and Scan is not available on ARM-based Windows 11 PCs, so on a Surface with a Snapdragon chip the feature simply is not there.

The steps, if you do have the hardware

1. Plug in the fax modem, let Windows install the driver, and connect the modem to the wall jack with a phone cord.
2. Open the Start menu, type Windows Fax and Scan, and launch it.
3. Click New Fax. On first run a wizard opens — choose Connect to a fax modem and name it.
4. Fill in the recipient's fax number, add a cover page from the template list, then type your message or use Insert → File to attach a scanned document.
5. Click Send. The Outbox shows progress; completed faxes move to Sent Items.

If you get "no dial tone", plug an ordinary telephone into the same jack and listen. Silence means the problem is the line, not Windows. More in our Windows Fax and Scan guide and the modem-free alternatives.

Method 4: How to Fax From a Mac

macOS has no built-in fax feature any more. Apple stopped shipping fax modems years ago and removed fax support from Printers & Scanners, so there is no "Fax" option waiting in System Settings on a modern Mac.

That leaves two options:

Use an online fax service (recommended). macOS handles PDFs natively — anything you can print saves as one with File → Print → PDF → Save as PDF. Upload that PDF in your browser, enter the number, send. Identical on Apple silicon and Intel Macs.

Attach a third-party USB fax modem. Possible, but it means finding a modem with a current macOS driver, wiring it to an analog line, and running the vendor's software — a last resort for a legacy workflow, not a practical answer.

Step-by-step for Apple hardware: how to fax on a Mac. Working from a portable machine, Windows or Mac? See how to fax from a laptop.

Method 5: Email-to-Fax — Can You Send a Fax Through Gmail?

Yes, through an email-to-fax gateway. Gmail has no fax function of its own; what makes it work is a provider that accepts an email on one side and places a fax call on the other.

The pattern is always the same:

1. Compose a new message in Gmail, Outlook, or Apple Mail.
2. Address it to <faxnumber>@<provider domain> — for example 15558675309@fax.example.com. Digits only, no spaces or dashes unless your provider asks for them.
3. Attach the document. The attachment becomes the fax. Some providers also render the email body as the cover page, so check before pasting anything sensitive into it.
4. Use the subject line as the fax subject, or leave it blank.
5. Send. Confirmation comes back to your inbox, usually within a couple of minutes.

Two caveats: the sending address normally has to be one you registered with the provider, or the gateway drops the message as spam, and an email attachment cap applies on top of the fax page limit. Full detail: how to send a fax from Gmail and how to fax from email.

Method 6: Fax From a Multifunction Printer Connected to Your Computer

If your office already has an all-in-one printer with a fax section — an HP OfficeJet, a Brother MFC, a Canon imageCLASS — you may be able to fax without walking to the machine. Most manufacturers ship a PC-Fax or Fax Send driver that appears in your list of printers.

1. Open the document in whatever application created it.
2. Choose File → Print, then select the printer entry named something like HP Fax, Brother PC-FAX, or Canon Fax.
3. Click Print. Instead of paper, a dialog asks for the recipient's fax number.
4. Enter the number, add a cover page if the driver offers one, and send.

The requirement everyone forgets: the printer needs a live analog phone line in its LINE port. USB or Wi-Fi carries the document to the printer; the phone line carries it to the recipient. No phone cord, no fax. More on this route: how to send faxes from a printer.

How to Fax a PDF From Your Computer

A PDF is the ideal thing to fax, and every method above accepts one directly. Upload it, enter the number, send — there is no conversion step to worry about, because the layout is already fixed.

Three checks before you send:

• Page size. Fax is built around US Letter and A4. A PDF sized for a photo print or a phone screenshot can arrive scaled or cropped.
• Contrast. Fax is 1-bit black and white, so light gray text, pale scans, and colour-coded tables lose information. Raise the contrast if the original is faint.
• File size. Compress anything over about 10 MB. The free PDF optimizer usually halves a scanned document with no visible loss.

If your document is a Word file, a photo, or a set of loose pages, convert it with the free document converter and combine the parts with the merge PDF tool so it goes as one transmission. Walkthrough: how to fax a PDF document.

How to Scan and Fax From a Computer

When the document only exists on paper, scan and fax from a computer in two steps: get it in, then send it.

Scanning it in. With a flatbed or sheet-fed scanner, scan at 200–300 DPI in black and white or grayscale and save as PDF. Higher resolution only makes the file bigger — fax transmits at roughly 200 × 200 DPI regardless. Windows users can scan in Windows Fax and Scan's Scan view even without a modem, since scanning and faxing are separate features of the same app. On a Mac, use Image Capture or Preview's File → Import from Scanner.

No scanner? Photograph each page in good, even light and straight on, then move the images to your computer — or use your phone's camera inside the mFax app, which scans and sends in one step.

Then fax it with any method above. The scan is now just a file. Detailed workflow: how to scan and fax a document.

Can I Fax From My Computer for Free?

The honest answer to "Can I fax from my computer for free?" is partly — and it is worth being precise, because "free fax from computer" is the most misleading phrase in this category.

What is genuinely free:

• A few trial pages. Most services front-load 3–10 free pages, enough for a single tax form or signed contract.
• Receiving. Several providers include free inbound faxing on pay-as-you-go plans — you pay only when you send.
• The software. Windows Fax and Scan is free with Windows; mFax for Windows is free to install from the Microsoft Store. In both cases sending is what costs money — a landline in one case, a subscription in the other.

What is not free: ongoing, unlimited faxing. Every fax places a real phone call over real telephone infrastructure, and someone pays for it. A service promising unlimited free faxing is either ad-supported with a shared number, about to introduce a paywall, or stamping its branding on your cover page — a poor look on a legal or medical document. Our roundup of the best free fax services compares what each one actually gives away.

How to Fax From a Computer Without a Phone Line

Every internet-based method here works without a phone line, because the phone call happens in the provider's data centre rather than in your building. Your document travels to the provider over an encrypted connection, and the provider's equipment dials the recipient's fax machine.

No landline needed: the web browser method, the mFax for Windows desktop app, and email-to-fax.

Landline still required: Windows Fax and Scan with a modem, and a multifunction printer with a cord in the LINE port.

The distinction matters more every year. VoIP replacements for POTS lines are unreliable for fax because packet loss and codec compression corrupt the tones a fax machine listens for — a fax that dies at page 4 of 6 on a VoIP line is the classic symptom. The workaround the industry standardised on is ITU-T Recommendation T.38, which carries fax as data rather than as audio, and it is what internet fax providers run on their side of the call. Internet fax avoids the problem entirely by never putting fax tones on your own connection. See faxing without a fax machine for the full picture.

What It Costs to Fax From a Computer

A single ten-page fax at a shipping store costs more than a month of an entry-level online plan. Full breakdown: how much it costs to send a fax.

When a Fax From Your Computer Fails

Faxes fail for boring, fixable reasons — these cover most of them.

One more that nobody catches: the wrong number. A fax cannot be recalled once sent, so confirm the digits before you press Send — especially on anything containing personal or medical information.

Is Faxing From a Computer Secure?

More secure than the machine in the corner of an office — provided you choose the method carefully. A paper fax sits face-up in an output tray where anyone walking past can read it; a fax sent from your computer lands in an account behind a login. A reputable service adds encryption in transit, encryption at rest, an audit trail of who sent what to which number and when, and a downloadable delivery receipt.

For medical records, transmission is only half of compliance: HIPAA requires a signed Business Associate Agreement, and consumer plans generally do not include one. If you handle PHI, use a business plan with a BAA — mFax Business includes one on every plan, alongside AES-256 at rest, TLS 1.2+ in transit, and SOC 2 Type II.

More Questions About Faxing From a Computer

Do I need to install software to fax from a computer?

No. The browser method installs nothing. On Windows 10 and 11, mFax for Windows is an optional free Microsoft Store download if you would rather have a real desktop app with drag-and-drop and clipboard paste.

Can I fax from my computer if there is no printer or scanner attached?

Yes. Nothing has to be printed. Any file already on the machine — or a photo taken with your phone and copied over — can be uploaded and sent as-is.

How long does it take to send a fax from a computer?

Roughly 30–60 seconds for one page, and about a minute for every three to five pages after that. Preparing the document usually takes longer than the transmission.

How do I know the fax actually arrived?

The receiving machine acknowledges the final page, and your service turns that into a dated receipt. Download and keep it — it is the only proof of delivery you will get.

Which method should I use if I only need to fax once?

The browser. It is the only route with no install, no hardware, and no account to maintain afterwards — open the composer, upload, send. Buying a $20–$50 modem or provisioning a landline for a single tax form never pays back.

Send Your Fax Now

For a one-off document, open mFax in your browser, drag the file in, type the number, and send — no install, no modem, no phone line, and it works the same on Windows, Mac, Linux, and ChromeOS.

If you fax regularly from a Windows PC, install mFax for Windows from the Microsoft Store instead: same account, same fax history, plus drag-and-drop, page editing, and signing with a pen or trackpad.

And when you need faxes coming back the other way, start with our guide to receiving a fax on your computer.

Related Guides

• How to fax from a PC — the Windows-only walkthrough
• How to fax from a laptop — the same methods, sized for portable hardware
• How to fax on a Mac — Apple-specific steps
• How to fax from iPhone — when you are away from the desk
• Best online fax services — compare providers before you commit