Firefox Download Browser: Install Firefox Safely in 2026

Downloading Firefox sounds like it should take thirty seconds, and most of the time it does. The trouble starts when a search result, a sketchy ad, or an old bookmark points you somewhere that isn’t actually Mozilla. This guide walks through the official firefox download browser process for Windows, Mac, Linux, and mobile, plus the install quirks Mozilla itself warns about — the Mac .dmg trap, the fake update scam, and what Firefox ESR is for. At the end, we’ll cover the one thing a fresh install can’t do: bring back tabs you had open in your old browser, and how BelayTab handles that from day one.

What Is the Official Way to Download the Firefox Browser?

The official Firefox download page is firefox.com, run directly by Mozilla. If you’ve bookmarked mozilla.org/firefox/new/ from years ago, that address now redirects to the same page, so either one gets you to the real thing.

From there, Mozilla offers builds for Windows (both 64-bit and 32-bit), macOS, Linux, Android through Google Play, and iOS through the App Store. You don’t need an account, a license key, or a credit card — Firefox has been free since it launched, and that hasn’t changed.

The risk isn’t the download page itself; it’s everything that tries to imitate it. Search ads that mimic Mozilla’s branding, “download now” buttons on unrelated software sites, and forwarded links in email are the usual traps. None of them are Mozilla, and none of them are a reliable source for a browser installer. If you’re ever unsure which browser you’re currently running or which version an old install left behind, a quick check with a tool like what’s my browser can settle the question before you start.

If you’re weighing Firefox against what you’re currently using, it’s worth reading a broader comparison first. Our Firefox browser review covers privacy and tab behavior in more depth, and the Firefox hub page rounds up the settings and shortcuts guides for the browser once it’s installed.

Firefox Download by Device: Quick Answer

The short version: use firefox.com on desktop, and your phone’s app store on mobile. Here’s how the install path differs by platform, at a glance.

Every path above ends with the same browser and the same account-free setup. What changes is who is responsible for future updates (Mozilla’s own updater, the Microsoft Store, or your Linux package manager) and that matters later when Firefox stops updating and you’re not sure why. We’ll come back to that in the update section further down.

How Do I Download and Install Firefox on Windows?

You have two supported paths on Windows: install from Mozilla’s own download server, or install from the Microsoft Store. Both are legitimate; the difference is mainly about who manages future updates.

The standard route is the one most people use, and it’s short enough to walk through in one pass.

1. Visit firefox.com. Any browser works for this step, including the one you’re replacing.
2. Click “Get Firefox” or “Download Firefox.” The installer downloads to your Downloads folder.
3. Open the installer file. Double-click it once the download finishes.
4. Accept the User Account Control prompt. Click “Yes” to let Firefox install for all users on the machine.
5. Wait for the Welcome to Firefox page. It opens automatically once setup completes.

That UAC prompt in step four matters more than it looks. If you decline it, or you run the installer from a non-administrator account, Firefox still installs — but only into your own user folder (C:\Users\<username>\AppData\Local\Mozilla Firefox\) instead of Program Files. That copy won’t show up for other Windows accounts on the same machine, which trips people up on shared or family PCs.

You might also see a SmartScreen-style warning during install on Windows 10 for the standard build. That’s expected behavior for a non-Store installer and isn’t, by itself, a sign anything is wrong — as long as the file came from firefox.com.

Prefer to skip Mozilla’s installer entirely? Search “Firefox” in the Microsoft Store app and install “Mozilla Firefox” from there instead. It requires Windows 10 or 11, and updates then flow through the Store rather than Firefox’s own updater.

How Do I Download and Install Firefox on a Mac?

Download the .dmg from firefox.com, open it, then drag the Firefox icon into your Applications folder — never run it directly from the disk image. That last part isn’t a suggestion; it’s a specific warning from Mozilla.

Don’t run Firefox straight from the .dmg. Mozilla’s own install guide is direct about this: opening Firefox from inside the mounted Firefox.dmg, or dragging the icon straight to your desktop instead of Applications, “can result in issues such as lost data and settings.” Always drag it into Applications first.

The Gatekeeper prompt you’ll see on first launch — something like “‘Firefox’ is an app downloaded from the internet. Are you sure you want to open it?” — is normal for any app downloaded outside the Mac App Store. Click “Open” to continue.

Once it’s running, if you’re coming from Safari or Chrome, this is also the right moment to check the best browser for Mac roundup if you’re still deciding, or the Mac-specific settings in the Firefox browser review if you’ve already committed.

How Do I Install Firefox on Linux?

You have more options on Linux than on any other platform, and several distributions already ship Firefox pre-installed, so you may not need to do anything at all.

If you do need to install it, Mozilla’s recommended method for Debian-based distributions is its own official .deb package through the Mozilla APT repository (not your distro’s default repo) added with a signed keyring, followed by a standard apt-get install firefox command. This ensures you get Mozilla’s build rather than a distro-patched or rebranded one.

Beyond that, you can install through:

• Your distribution’s own package manager, using its default repos.
• Flatpak, with flatpak install flathub org.mozilla.firefox.
• Snap, with sudo snap install firefox, including beta, edge/Nightly, or ESR-specific channel variants.
• A standalone tarball, extracted with tar xjf firefox-*.tar.bz2 and either moved to /opt system-wide or run directly from your own account without root access.

Worth knowing before you pick a method: automatic update checks through Firefox’s own “About Firefox” screen only work for builds downloaded directly from Mozilla. If you installed through your distro’s package manager, that manager handles updates instead, and Firefox’s built-in update option simply won’t appear. Keep that in mind so you’re not left wondering why Firefox never seems to prompt you.

What Are Firefox’s System Requirements?

Firefox will not install on Windows 8.1 or earlier, or macOS 10.14 or earlier. Those systems are pointed to Firefox ESR instead. Beyond those cutoffs, Mozilla publishes exact hardware minimums on a dedicated system requirements page rather than in the general install guides.

If you’re on an unsupported version of Windows or macOS, don’t try to force a workaround — install Firefox ESR instead, which we cover in more detail below. Trying to run an incompatible build tends to cause more install failures than it solves.

One thing that’s easy to overlook: your Firefox profile, where bookmarks, history, and saved logins live, is stored separately from the application itself. If you’re ever troubleshooting a move to a new machine, our guide to browser file locations explains where that folder sits on each operating system.

How Do I Download Firefox on Android or iPhone?

Install Firefox on a phone or tablet the same way you’d install any app: through your device’s official app store. There’s no standalone installer file for mobile, and there doesn’t need to be.

On Android, that means Google Play. On iPhone or iPad, it means the Apple App Store. Search “Firefox,” confirm it’s published by Mozilla, and install it the way you would any other app.

Mobile Firefox syncs bookmarks, history, and open tabs across devices through Firefox Sync once you sign in — a separate system from anything a desktop extension handles. If you want the specifics of setting that up, our Firefox Sync guide covers what it does and doesn’t carry over between devices.

It’s worth being clear about what this guide is and isn’t: BelayTab is a browser extension, and extensions don’t run on iPhone, iPad, or Android the way they do on desktop. If tab loss is a mobile-specific problem for you, Firefox Sync and the mobile browser’s own tab management are what you’re working with there — desktop is where an extension-based safety net like BelayTab applies.

How Do I Avoid Fake Firefox Update Scams?

You avoid them by remembering one rule from Mozilla directly: Firefox’s real updater never asks you to manually download and run a file. Any pop-up claiming an “urgent,” “important,” or “critical” update needs your action is not from Mozilla.

A real Firefox update never looks like a pop-up demand. Mozilla documents scammers redirecting users to fake pages that mimic an urgent Firefox update, sometimes pushing a malicious extension instead of an actual browser file. Their stated advice: never click these notices, and avoid downloads from unreliable sources altogether.

This kind of malvertising usually shows up while you’re browsing an unrelated site — a pop-up or full-page takeover claiming your Firefox is dangerously out of date. Firefox does have a legitimate in-browser “Heartbeat” notice for genuinely outdated versions, but that’s a subtle prompt inside the browser itself, not a page demanding you download something right now.

If you land on one of these pages, close the tab without clicking anything on it, and check your actual version through Firefox’s own Help menu instead — covered in the update section below. That’s the only place a real version check should happen.

This is also a good moment to mention that account security and tab safety are different problems. Even a perfectly legitimate Firefox stays vulnerable to a crash, an accidental “close all tabs,” or a bad update that resets settings. That’s a browser-behavior problem, not a scam-avoidance one, and it’s why a dedicated recovery layer matters even when you’ve downloaded everything correctly. Our recovery screen guide walks through what that looks like day to day.

Should I Use Firefox ESR Instead of Regular Firefox?

Use Firefox ESR if you’re managing Firefox for an organization, a lab, or a fleet of machines that need extended support rather than the fastest feature release cycle. For a personal computer, the regular release is almost always the right pick.

ESR stands for Extended Support Release, and Mozilla built it specifically “for organizations, including schools, universities, businesses and others who need extended support for mass deployments.” It’s based on the same underlying code as the regular desktop release, just held to a slower, more predictable update rhythm.

There’s one case where ESR isn’t optional: if you’re on Windows 8.1 or earlier, or macOS 10.14 or earlier, the regular Firefox release won’t install at all, and ESR is Mozilla’s documented path forward for those systems. Outside of that, most home users get more value from the standard release, since it reaches new features and fixes faster. If you administer machines for a school or small business, though, ESR’s predictable update schedule is usually worth the tradeoff — fewer surprise UI changes mid-semester, at the cost of waiting longer for new features.

How Do I Update Firefox and Protect My Tabs Going Forward?

Firefox updates automatically in most cases, and you can trigger a manual check anytime through the menu button, then Help, then “About Firefox.” That window shows your current version and starts an update check the moment you open it.

Once an update has downloaded, click “Restart to update Firefox” to apply it — updates only take effect after a restart, not before. On Linux, this automatic check only appears for builds downloaded directly from Mozilla; package-manager installs update through the package manager instead, and the same applies to Microsoft Store installs, which update through the Store. If an update ever fails outright, Mozilla’s own fix is to close Firefox, re-download the installer from firefox.com, and run it again — your bookmarks, history, and other data are preserved through that process.

None of that touches your open tabs directly, though. Firefox’s Session Restore feature (menu button, then History, then “Restore Previous Session”) and the Ctrl + Shift + T (Cmd + Shift + T on Mac) shortcut to reopen your last closed tab both work well for routine closes. What they don’t cover: Private Browsing windows, which are deleted permanently by design, a fresh install with no prior session to restore, or a full switch to a different browser entirely.

That gap is exactly where BelayTab fits in, and it works across Firefox, Chrome, Edge, Brave, and several other Chromium browsers plus Safari on Mac.

• Save. One click or Ctrl + Shift + S (Cmd + Shift + S on Mac) saves a window, selected tabs, or all windows as a named session, keeping tab groups, pinned tabs, and order intact.
• Restore. Bring a session back into a new window, the current window, or restore a single tab, with large sessions opening in batches so nothing overwhelms your machine at once.
• Import. Bring in sessions from OneTab, Session Buddy, Tab Session Manager, Tablerone, or a plain URL list — useful the day you switch browsers for good.

BelayTab is free, doesn’t require an account, and automatically snapshots each open window every five minutes, and again the moment you close a window, so there’s no habit to remember. Restoring a session never overwrites an older one. It just adds a new version to that session’s history, up to the last 20 versions. If you’d like the setup steps, how to save tabs in Firefox and other browsers and restoring closed tabs both walk through the extension side by side with what Firefox does on its own.

Once you’re settled into Firefox day to day, it’s worth reading up on Firefox tabs and tab groups, the Firefox shortcuts guide, and what to do if Firefox keeps crashing so you have Mozilla’s own troubleshooting order on hand before you need it.