Build A Mock API
Using Beeceptor, a mock API endpoints is up and ready to be consumed in seconds - in short, No Coding Required. Just define API path, response and start hitting from code.
Intercept & Inspect - Proxy Setup
Wrap an existing APIs endpoint with Beeceptor endpoint and inspect all the traffic going to original API. Beeceptor acts as a proxy-server and helps in debugging headers and body for HTTP requests.
Selectively Mock API Calls
When you specify a target endpoint, you can use rules to mock a few calls. When a rule is matched, Beeceptor gets you what is needed. If no rule matches, the request is forwarded to original target and your application works as usual.
UI Development
Is the data contract ready between UI and API developer? Just mock the response and unblock UI developers.
CORS Support
Beeceptor, comes with CORS support and all origins are accepted out of the box. (Access-Control-Allow-Origin: *).

OPTIONS calls will get '200 OK' always.
Single Page Application - SPA
One great usage is during SPA development. You need first few ajax request to initialize the page and later mocking new calls. Beeceptor can route requests to original target without breaking your flow.
Integration Tests
Consider you are working on API 'A', and downstream micro-services are 'B' and 'C. Beeceptor can help you mock B and C to test paths that were not possible before. E.g. when B times-out or erred, how does A behave?
Load Testing an API
When your API consumes 3rd party APIs, load testing is difficult. Just wrapping an 3rd party API and enable/disable rules helps here. E.g. sending a transactional emails when your API is called - why not mock Sendgrid/SES/MailGun/PostMark APIs.
Production vs New Code
You can switch the target endpoint anytime. This helps you validate a test against deployed code vs new code in development. E.g. does this GET call return same data for new vs old code?
Webhook Development
Either you are consuming a webhook or building one, you shall need to inspect and debug HTTP calls. Beeceptor give you an endpoint that you can configure at any service.

E.g. Stripe, Zoho, Sendgrid, Jira, Gitlab, IFTTT, Zapier, etc.
Beeceptor demo