7 SSL Certificate Problems That Kill Trust
Expired certs, mismatched domains, weak encryption. A practical checklist for catching SSL issues before your users do.
API Guides
How specific APIs behave in practice, and what to check before you rely on them.
API Guides 15
DNS Lookups: A Developer's Debugging Guide
DNS problems cause connection failures and email issues. Learn how to use DNS lookups to diagnose problems faster.
Currency Conversion: Handling Exchange Rates Correctly
Exchange rates change constantly. Learn how to handle currency conversion in applications with accuracy and reliability.
WHOIS Data: Domain Intelligence for Business and Security
WHOIS data reveals domain ownership, age, and infrastructure. Use it for lead qualification, research, and fraud detection.
How Accurate Is IP Geolocation? We Tested 2,852 IPs
We checked 2,852 RIPE Atlas probes with known locations against our IP lookup. Country: 99.4%. Median error: 13 km. One in five off by 100 km or more.
QR Codes Are Back (And This Time It's Different)
Remember when QR codes were a punchline? Now they're everywhere. Here's why this time it stuck.
What Your User Agent String Reveals
Every HTTP request announces who you are. Here's what's in that string and what you can do with it.
The Phone Number Validation Rabbit Hole
Validating phone numbers seems simple until you try it. Here's what makes it surprisingly complex.
Building Health-Conscious Apps With Air Quality Data
Air quality affects millions of users. Here's how to integrate environmental health data meaningfully.
Why Your Sentiment Analysis Is Wrong
Sentiment analysis is powerful but often misused. Here's how to use sentiment data effectively.
QR Codes: More Useful Than You Think
URLs, WiFi passwords, contact cards, payment links—QR codes do more than you'd expect. Here's how to generate and read them programmatically.
REST vs GraphQL: Which Should You Use?
Skip the theory. Here's when to use REST endpoints and when GraphQL actually makes sense.
Real-Time APIs: WebSockets vs Server-Sent Events
Compare WebSockets and Server-Sent Events for real-time data. Learn when to use each and how to implement them.
Geocoding API Guide: Convert Addresses to Coordinates
Learn how to convert addresses to coordinates and vice versa using geocoding APIs. Practical examples and best practices.
Token-Based API Billing: How It Works
Understand how token-based billing works for APIs. Learn credits, usage tracking, and how to optimize your API costs.