How Callio Works

One API key to discover, authenticate, and call any API. Built for developers and AI agents.

Watch: How Callio Works

Browse the Marketplace

Explore APIs and skills organized by category. From data enrichment to web scraping, email services to AI models — find exactly what you need.

Browse APIs

📧 SendGrid

🤖 OpenAI

💬 Slack

📊 Analytics

🔍 Scraper

🌐 Globe

Get One API Key

Generate a single Callio API key from your dashboard. This key authenticates you across every API in the marketplace. No more juggling dozens of keys.

Manage keys

Your Callio API Key

callio_a1b2c3d4e5f6g7h8i9j0k1l2

Works with every API — no extra keys needed

Call Any API

Route your requests through the Callio proxy. We handle authentication, rate limiting, and error handling. Your agent gets a unified interface.

Read the docs

curl -X GET \
  "https://callio.dev/api/proxy/jsonplaceholder/posts/1" \
  -H "Authorization: Bearer callio_..." \

# Response
{
  "data": [...],
  "has_more": false
}

Why developers choose Callio

One Key for All

Stop managing dozens of API keys. One Callio key unlocks every API in the marketplace.

Secure by Default

Provider keys are encrypted and never exposed. Callio handles auth injection at the proxy level.

Zero Config

No SDK, no client library. Just HTTP requests through the proxy with your Callio key.

Unified Interface

Every API follows the same proxy pattern. Consistent error handling and response format.

Agent-Ready

Built for AI agents. One config block gives your agent access to the entire API ecosystem.

Discovery

Browse, search, and evaluate APIs before integrating. Interactive playground to test live.

Ready to get started?

Create an account, generate your API key, and start making calls in under 2 minutes.

Create Account Read Docs