Is Slither.io safe? Is it a virus? Ads, installers and how to remove them

Yes for the game page, with limits. In our check on 4 October 2026 the start page at slither.io asked for no notifications, opened no pop-ups, redirected to no other domain and registered no service worker.

We did not play a round, so we cannot speak for ads that appear in the game, for other countries or for the phone apps. The page loads over plain HTTP, and it uses Facebook and Twitter widgets and a Google tag.

Play it in the browser, type nothing private into it, and install nothing that carries its name. The risk is not the game but the installers, add-ons and look-alike sites that borrow the name.

The game page has no virus: it is a web page that runs in the browser tab and installs no program. Our test on 4 October 2026 saw no download, no pop-up and no redirect to another domain. What can carry a virus is something that only uses the name:

• a Windows installer called Slither.io or Slither IO (32 bit)
• a game add-on from an unknown developer
• a copy of the site

Our 2021 report warned about those, not about the page itself. If you ran an installer, uninstall it from Installed apps, run a full Microsoft Defender scan and an offline scan, and reset your browser.

Because the page uses plain HTTP, not HTTPS. We requested https://slither.io/ on 4 October 2026 and the server sent the browser on to http://slither.io/?a, so the page and its images are not encrypted, and browsers label that "Not secure". It does not mean the page infects you.

It means someone on the same Wi-Fi network could read or alter what loads, so do not type a password or private details into it, and avoid playing on public Wi-Fi without a VPN. The game asks only for a nickname.

We did not test the game for faults, so we cannot give a cause from our own checks. The old guide and readers mention lag, and the game needs a steady connection because it is a multiplayer game on remote servers.

Reload the page, choose another server with the Choose Server button in the corner, close other tabs and downloads, and try another browser. Turn off any game extension you added, because add-ons that change the page can break it. Do not install a desktop version to fix it: that is the file the old guide warned about.

If you only played in the browser, there is nothing to uninstall. If you ran an installer, open Settings > Apps > Installed apps in Windows 11 (Apps & features in Windows 10), sort by install date and uninstall anything named Slither or installed when you ran the file.

Then remove any game extension in your browser's extensions page, run a Microsoft Defender full scan and an offline scan, and use the browser reset step in this guide if the start page, search engine or toolbars changed.

We found no Windows program on the game page we tested; the page is a web game, and it carries a tag for an App Store app. The old guide warned that desktop versions found online might contain suspicious files, and a screenshot in it shows entries called Slither IO (32 bit).

Treat any Windows installer with the name as unverified: it did not come from the page we tested. Play in the browser instead. If you installed one, follow the uninstall and scan steps in this guide.

We did not test any, so we cannot say. The old guide named Slither.io Plus, Amazing Slither, Slither.io Mods, Zoom, Unlock Skins and Bots as examples of what the Chrome Web Store offered. Any extension can be harmless or not, and what matters is its permissions.

One that can read and change data on all the sites you visit can show ads or watch your browsing, whatever game it names. Read the reviews and the developer, refuse broad permissions, and remove any add-on you do not recognise at chrome://extensions.

Yes, to a limited extent, according to its own privacy page which we read on 4 October 2026. The servers log your IP address, device characteristics and browser type, and the nicknames you enter.

The page says this could be tied to you if the logs are demanded in legal proceedings, and that cookies, web beacons or other tracking and third-party vendors' cookies may be used.

The page is only a few sentences and does not say how long logs are kept. Use a nickname that is not your real name and avoid typing private details into the game.

On the start page we did not see it: no redirect to another domain and no pop-up opened on 4 October 2026. We did not play a round, so ads inside a game or in another country remain unchecked.

Redirects while you play usually come from an extension, an installed program or a look-alike site, not from the real page. Check the address bar, remove extensions you do not recognise, uninstall any Slither.io program from Installed apps, and reset your browser. Never click Allow on a page that asks for notifications to let you continue.

Fortect scans Windows for malware and unwanted programs and repairs the system files and settings they change, and its free scan shows what it finds on your PC before you decide anything.

For Slither.io, follow the plan above as well: the browser steps take back permissions and settings that no scanner treats as a threat, and uninstalling the program that brought it removes the source.

Run Microsoft Defender's full scan and, if anything was found, its offline scan as a second opinion. If the symptoms are gone after the plan and both scans are clean, there is nothing more to do.