# URL Scanner — Sylon

> Checks where a link actually goes — four sources, cheapest first, and the free ones answer almost everything.

Canonical page: https://sylon.app/features/url-scanner

## Overview

A link is text until somebody opens it. The URL Scanner is what decides where it actually goes — following redirects, resolving invites, and asking four independent sources whether the destination is known to be a scam. It runs inside Ad Protection because a link to a phishing page is an advertisement in the sense that matters, and it acts through that system's punishment and log channel rather than inventing a second set.

## How it works

1. **Four sources, in order of cost** — A list held in memory, then Sylon's own reputation table, then a free aggregator, then VirusTotal. Each is only asked what the ones before it could not answer.
2. **The free ones do the work** — The first two need no network call at all. Most scam links never reach the third source, and a raid posting the same domain a thousand times costs a thousand hash lookups and zero requests.
3. **Failure means unknown, never clean** — A timeout, a rate limit or a service having a bad afternoon leaves the decision to the analyser. No source is ever allowed to wave a link through by failing.

## Key capabilities

- About 44,000 known phishing domains held in memory, updated within seconds over a live feed
- Redirect chains followed hop by hop, so a shortener cannot hide the destination
- Discord invites resolved to the server behind them
- The destination's own title and description read and handed to the analyser
- Roughly 390,000 more domains covered by a free aggregator
- VirusTotal's seventy antivirus vendors, when a key is configured
- Every source switchable per server, with the rest continuing to run
- Mainstream and first-party domains protected from every source at once

## Frequently asked questions

### Where do I find it in the dashboard?
Under Protection, next to Ad Protection — it is that system's link half. The toggle that stops it entirely is Ad Protection's own, because the scanner decides where a link goes and Ad Protection is what acts on the answer.

### Do I need a VirusTotal key?
No. The first three sources need no key and no configuration, and between them they catch the overwhelming majority of Discord scams. A key adds a fourth opinion for the links nothing else recognised.

### Can a bad list entry get a real site blocked?
Not a mainstream one. Discord, the major platforms, media hosts, URL shorteners and Sylon's own domains are excluded before any source is consulted and again on the way back, so no third party can cause them to be blocked here.

## Related features

- https://sylon.app/features/ai-ad-protection
- https://sylon.app/features/spam-protection
- https://sylon.app/features/server-guard

Keywords: discord url scanner, discord phishing protection, discord malicious link detection, discord scam link blocker, virustotal discord bot