Blog
Deep dives on APIs.
- Best API Monitoring Tools in 2026, RankedThe best API monitoring tools in 2026, ranked, with free tiers verified, plus what our weekly uptime sweep of 1,569 public APIs says actually breaks.
- Best API Testing Tools in 2026: 10 RankedThe best API testing tools in 2026, ranked, with each one's real free-tier ceiling checked on the publish date and the CORS trap that breaks browser-based clients.
- API Rate Limiting: Handle 429s, Then Set Your OwnHow API rate limiting works from both sides: reading limit headers, backing off correctly from a 429 against real public APIs, and setting limits on your own.
- REST API Best Practices: What 1,613 APIs DoThe REST API best practices that matter, each one measured against the 1,613 public APIs in our directory, so you can see which are followed and which are ignored.
- Free API Hosting: 7 Options and Their Real LimitsWhere to deploy an API for free, with each provider's actual free-tier ceiling on requests, CPU and idle time, checked against their own pricing pages.
- API Authentication Methods: What 1,625 APIs UseThe four API authentication methods that matter, compared, plus live data on what 1,625 public APIs actually use in production.
- How to Test an API (Step by Step, With Free APIs)A practical guide to testing an API: manual curl checks, the tools worth using, what every test should assert, and free public APIs to practise on.
- API Versioning Best Practices: What 225 Public APIs DoWe read the OpenAPI specs of 225 public APIs: 62% put the version in the URL, 1 uses a header, 37% declare none, and only 8% mark anything deprecated.