Struggling with IP geo-targeting accuracy: why are users from other countries seeing local content?

Hey everyone,

Following up on the discussion about IP address lookup accuracy. We're trying to implement a basic geo-targeting feature for our SaaS to show region-specific pricing and content. The goal is to provide a more personalized experience, but we're hitting a wall.

Despite using a reputable IP geolocation API (first MaxMind GeoLite2, then we tried IPinfo.io for comparison), we're consistently seeing users from outside our target regions (e.g., US users) being served content meant for a different country (e.g., UK pricing). This is causing a lot of confusion and a pretty poor user experience, which is the last thing we want.

Here’s what we’ve tried so far to troubleshoot this IP resolution issue:

• We've implemented server-side IP lookup on the initial request to ensure we're getting the IP as early as possible.
• We've double-checked our X-Forwarded-For headers to make absolutely sure we're getting the true client IP behind Cloudflare/CDN and not just the CDN's edge IP.
• We've manually tested with various VPNs and proxies to simulate different locations – sometimes it works perfectly, sometimes it completely misses the mark.
• We’ve meticulously verified our content delivery logic; it seems straightforward: if ip_country == 'US' show US content. No complex nested conditions that could be causing issues.

We've made some specific observations that might help narrow down the problem:

• It's not happening to all non-target users, but a significant percentage are affected. Enough to be a real concern.
• Sometimes, simply refreshing the page multiple times can mysteriously correct the content to the user's actual location. This suggests a caching or transient data issue, but we can't pinpoint it.
• We've seen US IPs resolve to UK, Germany, or even Australia. These are pretty substantial misidentifications.

We're really seeking advice on a few things:

• What are the most common pitfalls when implementing IP geo-targeting for content delivery that we might be overlooking?
• Are there specific headers or CDN configurations (beyond X-Forwarded-For) we should be looking at more closely? Maybe something specific to Cloudflare or similar services?
• Could this be related to specific ISPs or mobile carriers known for having less accurate IP resolution data?
• Any robust debugging strategies beyond manual VPN testing? We need something more systematic to track down these discrepancies.

Thanks in advance for any insights!