API Request Tester
Send HTTP requests to any API endpoint instantly — no install needed
Test any REST API endpoint without installing Postman or writing code. Send requests with custom headers, authentication tokens, and JSON payloads, and inspect the response status, headers, and body in real time.
When to Use a Browser-Based API Tester
A browser-based tester is fastest for:
- Quick one-off API calls to verify an endpoint works
- Debugging a specific request/response pair
- Checking authentication headers before writing code
- Testing webhook endpoints you've set up
For collections, environments, and team collaboration, Postman or Insomnia is better suited.
Request Components This Tool Supports
- Methods — GET, POST, PUT, PATCH, DELETE
- Headers — Content-Type, Authorization, custom headers
- Auth — Bearer token, Basic auth, API key
- Body — raw JSON, form data, URL-encoded
- Query parameters — built visually or in the URL
Understanding API Responses
| Status Code | Meaning |
|---|---|
| 200 OK | Success |
| 201 Created | Resource created |
| 400 Bad Request | Invalid input — check your payload |
| 401 Unauthorized | Missing or invalid auth token |
| 403 Forbidden | Authenticated but no permission |
| 404 Not Found | Endpoint or resource doesn't exist |
| 429 Too Many Requests | Rate limit hit |
| 500 Internal Server Error | Server-side bug |
Related Reading
This tester comes up constantly in my own build process — verifying a GoHighLevel or Retell AI webhook response before wiring it into Make.com. Make.com HTTP Module Tutorial and API Automation for Businesses cover the broader context of connecting APIs like this into a real workflow.
Building API Integrations
If you're connecting third-party APIs to your CRM, automations, or internal tools, a well-structured integration handles errors, retries, and rate limits gracefully — this is core to the automation work I build for clients. Book a consultation for production-grade API integration work.
Want this built against your real numbers?
A 30-minute call to scope the workflow, agent, or automation you actually need.
More developer tools
All tools.env Manager
Validate, compare, and generate templates for your .env files — without exposing secrets
.gitignore Generator
Generate a complete .gitignore for any stack — languages, frameworks, and IDEs covered
API Mock Server
Create live mock API endpoints with custom JSON responses in under a minute
Base64 Encoder/Decoder
Encode or decode any Base64 string instantly — no install, no login
Cron Expression Generator
Build any cron schedule visually and get the correct expression instantly
Docker Compose Generator
Build a complete docker-compose.yml for any stack in seconds — with health checks included
Have a workflow that's burning hours every week?
Bring me one real bottleneck. I'll tell you whether it's worth automating, and what it would take.