But APIs are more than just technical plumbing. They shape industries, fuel innovation, and have transformed the internet as we know it.
In this blog, we’ll explore 10 fascinating facts about APIs that highlight their power, versatility, and growing importance in modern development.
- APIs Power Over 80% of Web Traffic
That’s right—more than 80% of all web traffic today is API traffic. Behind every app and website are API calls fetching data, posting updates, and enabling dynamic features. From Netflix streaming to Google Maps navigation, APIs are the silent backbone of the internet.
- The First API Was Launched in 2000
While the concept of APIs existed in programming for decades, Salesforce launched the first modern web API in 2000. This marked the beginning of APIs as a business tool. Shortly after, Amazon, eBay, and Google followed suit—kickstarting the API economy.
- Public APIs Are Big Business
There are now over 50,000 public APIs available on directories like RapidAPI, ProgrammableWeb (archived), and GitHub. Major companies like Stripe, Twilio, and Spotify have built entire business models around developer-friendly APIs.
In fact, Twilio’s revenue was over $4 billion in 2023, almost entirely through APIs!
- REST Isn’t the Only Game in Town
Most developers are familiar with REST (Representational State Transfer) APIs, but it’s not the only style. Others include:
- GraphQL – lets clients request only the data they need
- gRPC – ideal for high-performance microservices
- SOAP – still used in many legacy enterprise systems
Each has its own use cases and trade-offs.
- APIs Aren’t Just for Developers
APIs are increasingly being used by non-developers through low-code and no-code platforms like Zapier, Make, and Airtable. These tools abstract API calls into user-friendly workflows, allowing anyone to automate tasks and integrate services without writing a single line of code.
- Badly Designed APIs Can Cause Major Failures
Insecure or poorly documented APIs can lead to serious vulnerabilities. In 2018, Facebook’s API flaw exposed personal data of nearly 50 million users, leading to significant reputational and legal consequences.
APIs need to be treated as products—with proper authentication, versioning, monitoring, and security baked in.
- APIs Can Drive Product-Led Growth
Many companies now offer API-first products, allowing developers to integrate services programmatically and build custom solutions. Companies like Slack, GitHub, and Notion offer robust APIs that contribute to community-driven innovation and wider adoption.
When developers love your API, they become your strongest advocates.
- APIs Enable the Microservices Revolution
Modern cloud-native architectures are increasingly microservices-based, where each service handles a specific task and communicates via APIs. This makes systems more scalable, modular, and easier to maintain.
For example, an e-commerce platform might have separate services for payments, inventory, and user management—all communicating through internal APIs.
- APIs Can Be Monetized
Companies are turning APIs into revenue streams by offering them as API products with pricing tiers, usage limits, and paid plans. Examples:
- Stripe charges per transaction
- OpenAI offers APIs with usage-based pricing
- Google Maps API is billed by map loads or request volume
API monetization is a smart way to scale B2B SaaS offerings.
- API Documentation is as Important as the API Itself
Even the most powerful API is useless without good docs. Clear, well-structured, and interactive documentation can make or break developer adoption.
Tools like Swagger (OpenAPI), Postman, and Redoc help developers create and share easily navigable API documentation. Great documentation turns an API into a developer-friendly product.
Final Thoughts
APIs are not just technical tools—they are strategic assets. From improving internal system design to enabling global-scale integrations, APIs play a central role in software innovation. As the API economy continues to grow, developers and businesses that invest in smart API design, security, and usability will have a significant competitive edge.
Whether you're building a startup, scaling enterprise software, or experimenting with side projects, understanding how APIs work and evolve is a must in today’s connected world.
Read more- https://keploy.io/blog/community/fun-facts-about-apis