Modern software monetization has moved away from offline key files. uTorrent Web uses online account-based licensing. Here is how it actually works:
Therefore, a standalone license file is technically impossible for the current uTorrent Web build. If a website offers a "key file," they are lying or distributing malware. utorrent web license key file top
If you cannot afford Pro, switch clients. These are 100% free, open-source, and have zero "license key" nonsense: Modern software monetization has moved away from offline
All of these offer what uTorrent Web Pro does (streaming, no ads, high speed) for $0, legally. All of these offer what uTorrent Web Pro
Another "top trick" is adding 127.0.0.1 license.utorrent.com to your hosts file.
Why it fails: uTorrent Web won't downgrade to offline mode; it simply shows "License unreachable" and stays free.