# Guides
> Short notes on IP addresses, wrong geolocation, CGNAT, Indian ISPs, WebRTC, and DNS leaks.
- [IP location wrong? How to fix it](https://ipinfo.fyi/guides/wrong-location): Why an IP’s city is wrong, when a correction helps, and the forms for MaxMind, IP2Location, IPinfo, DB-IP, and Google.
- [CGNAT, in plain language](https://ipinfo.fyi/guides/cgnat): How to tell if your IPv4 address is shared, and what IPv6, Tailscale, and a tunnel change.
- [Asking an Indian ISP for a public address](https://ipinfo.fyi/guides/static-ip-india): What to check, and what to ask Jio, Airtel, BSNL, and ACT for, without a made-up price list.
- [Shared IPs, VPNs, and trading access](https://ipinfo.fyi/guides/trading-and-shared-ips): A careful note for people told they need a static IP. This is not a SEBI ruling and not advice about any firm.
- [WebRTC leaks and timezone mismatches](https://ipinfo.fyi/guides/webrtc-leaks): What a browser leak test can and cannot prove about a VPN.
- [Publish a geofeed for your prefixes](https://ipinfo.fyi/guides/geofeed): A short RFC 8805 geofeed, and where to put it so geolocation vendors pick it up.
- [What a DNS leak test actually checks](https://ipinfo.fyi/guides/dns-leak): A DNS leak is a lookup that bypasses your VPN. This site does not run that test, and this page explains what would, and what the WebRTC check is instead.