Blog
Practical notes for network and browser checks.
Clear guides for the tools on CheckMySys.
What Your IP Address Actually Reveals About You
Your IP address doesn't contain your location, your name, or your browsing history. Here's what it does reveal, how geolocation databases work, and what VPNs actually change.
How Internet Speed Tests Actually Work
Speed tests measure TCP throughput to a specific server, not some absolute property of your connection. Here's what's really happening when you click 'Start Test' — and why results vary.
Is Your Password Secure? The Math Behind Entropy
Password entropy measures how hard a password is to guess. Here's how to calculate it, why length beats complexity, and what 'estimated crack time' actually assumes.
Browser Fingerprinting — What You Leak Without Knowing
Your browser reveals a surprising amount of identifying information without cookies or logins. Here's how fingerprinting works, which signals matter most, and what actually reduces your uniqueness.
DNS Record Types Explained — A, AAAA, MX, TXT, and More
A practical guide to DNS record types: what each one does, when you need it, and real-world examples from setting up email to verifying domain ownership.