TLDR: Need to check an onion link fast? Skip the Tor bundle setup and use browserling.com/tor. I and my team run live onion browsers in the cloud, so you can test onion sites instantly from any device.
Onion Link Checker – What Is It?
An online onion link checker is a tool that helps you verify whether a .onion website is working or is offline. Since .onion sites can only be accessed through the deep web network, it connects to deep web and tests the link for you. It's useful if you're trying to visit a deep web site but aren't sure if it's down or just not loading on your end.
How Does an Onion Link Checker Work?
An online onion link checker works by using a cloud-based Tor browser to connect to the onion network and verify if a .onion site is online. As regular browsers can't open .onion links, a checker uses a preconnected Tor browser session to test if the website loads properly. If the site is down, the checker will return an error message, such as "Onion Site Not Found" or "Unable to Connect".
What Are Onion Link Checker Use Cases?
Checking if an Onion Site is Online
If you're trying to visit a .onion site and it's not loading, an onion link checker can show whether the site is down or if the issue is on your end.
Verifying a Dark Web Link Before Using Tor
You don't need to install the Tor browser bundle to check if an onion link works. An online onion link checker can save time by quickly testing if the site is reachable.
Avoiding Fake or Malicious Onion Links
Scammers create fake onion links that look like real dark web sites. An onion link checker helps verify if a link is legitimate before you visit it.
Detecting Onion Link Expiration
Some .onion addresses disappear after a while, especially those using temporary hosting services. An onion link checker helps you confirm if a link is still valid.
Monitoring Hidden Services for Uptime
If you run a dark web service, an onion link checker can alert you when your site goes offline so you can fix it.
Checking If a Site Requires Authentication
Some onion sites require special access keys. An online onion link checker can help determine if a site is behind an auth wall.
Checking If a Site Uses v2 or v3 Onion Protocol
Older v2 onion links are no longer supported. An onion link checker can tell you if a link is outdated and needs a v3 version.
Testing for Onion Network Issues
If multiple onion sites aren't working, an onion link checker can help determine if the onion network itself is experiencing problems.
Verifying If an Onion Mirror is Working
Many popular sites like the BBC and ProtonMail have multiple onion mirrors. An onion link checker can help check if mirror sites are available and you can also test which of the mirror sites is the fastest.
Testing Onion Site Speed and Response Time
Some onion services load painfully slow. An onion link checker can give a rough idea of how fast a site responds before you waste time waiting.
What is Browserling?
Browserling is a general-purpose browser testing service, which features an onion link checker. It helps users verify whether .onion websites are online and accessible without extra downloads. Browserling is useful for checking if your dark web site is available, detecting expired and broken onion links, and finding working onion sites.
Who Uses Browserling?
Browserling has now become the online onion platform of choice for web developers, security researchers, and intelligence analysts, and it's used by hundreds of thousands of users around the world every month. Browserling's customers include governments, states, cities, banks, stock exchanges, universities, newspapers, Fortune 100, Fortune 500 companies, and private multi-billion dollar companies.

Happy browsing!