Fintech APIs are tricky; payments, KYC, wallets, ledgers, refunds, transaction verification...everything needs to work perfectly. Even the smallest bug can break a customer payment or cause a compliance issue. This is why proper API testing matters more in fintech than anywhere else.
In this guide, I’ll show you exactly how to test your fintech APIs on KushoAI. We’ll upload your API, set up environments, handle auth, run tests, and even build complete end-to-end payment flows.
Fintech’s Typical API Workflow
Fintech systems rely on tightly connected API chains. A single customer action, such as onboarding or making a payment, triggers multiple backend services that interact in sequence.
A standard fintech workflow looks like this:
Customer Onboarding: Capture user details. Trigger the KYC process. Receive verification callbacks.
KYC/AML Checks: Connect with external verification providers and government systems.
Risk & Credit Scoring: Pull customer information, risk engines, and generate score decisions.
Payment Authorization: Validate tokens, initiate transactions, and confirm status with payment gateways.
Ledger & Reconciliation: Update balances, record entries, and match settlements across internal + partner systems.
Why Testing Fintech APIs Is Hard
Unlike typical SaaS workflows, fintech systems move money, store identity data, and depend on third-party infrastructure. That makes testing objectively harder. A few unique complexities include:
Multi-Vendor Integrations: Fintech teams depend on banks, KYC vendors, payment gateways, and loan servicing partners, each with different response formats, SLAs, and failure modes.
Regulated Test Data: You can’t freely use production-like customer data due to compliance rules (KYC data, PAN/Aadhaar, banking details). This makes it difficult to create realistic test cases.
Versioned APIs: Banking and payment APIs evolve frequently, and even small contract changes can break critical workflows.
High Reliability Requirements: In fintech, API failures directly impact money movement, compliance, customer trust, and operational losses.
With so many moving parts in fintech workflows, you need a testing approach that adapts to complexity. Here’s how KushoAI helps you do that effortlessly.
How Fintech Teams Can Test Their APIs Using KushoAI – Prerequisites
- Your fintech APIs (Postman collection, URL, OpenAPI spec or cURL)
- KushoAI account (free, no credit card required)
Step 1: Upload your APIs
To get started with testing, upload your APIs to KushoAI and provide the necessary fields, such as request body, query params, etc. After providing the required information, click the “Generate” button to generate the API tests.
Step 2: Review and Run Your Generated Tests
After clicking on “Generate”, you will be redirected to the Test Suite page, which will display all your tests. You can run the test using the “Run” button on the right side of the Tests’ name. To check the request body, click on the “details” dropdown.
Step 3: How to Generate Assertions
To generate Assertions for your Test, click on the “Assertions” button and click on “Generate using AI”. When the Assertions are generated, you can edit them and click on “Save and Run”.
To generate assertions for all the tests, click on “Generate Assertions” located beneath the search tab. Keep in mind that you need to run all the tests in order to create assertions in bulk, or KushoAI will automatically handle that. You can generate and execute the tests by using the “Run All Tests” option.
Step 4: Security Testing
Now that we have covered the Function testing part, you can create security tests for your API as well.
KushoAI's Security Testing proactively identifies vulnerabilities in your APIs and applications by simulating real-world attack scenarios. This helps ensure resilience against common threats like SQL injection, XSS, and insecure authentication, allowing you to confidently ship your product, knowing it's safeguarded before production.
You can access it by clicking on the “Security” button ,as shown in the image below. Click on “Generate Security Tests”.
After the security tests are generated, you can run them just like the functional tests, as shown above. You can also add assertions.
Step 5: End-to-End Testing
To create a workflow that connects your APIs, enabling the development of complex, sequential test scenarios, you can utilize End-to-End testing.
In this approach, the output of one API serves as input to subsequent APIs, enabling thorough integration testing. Navigate to the left panel, click on "E2E test suite," and then select "Create" to initiate a new End-to-End test suite.
Create a test suite, name it and provide a description. Click on “Create”.
You will be redirected to the Workflow window.
Create your Workflow by selecting an existing API or creating a new one.
You can also manage your tests using the hamburger button on your API. After your workflow is created, click on “Run”.
After clicking on “Run”, your workflow will be executed, and a window will pop up with your result. From there, you can check the request, response, and generate assertions by clicking on the “Generate button” for individual APIs or clicking on Assertions to generate for all.
Fintech-focused Use Cases for KushoAI
Some fintech use cases are:
- Testing UPI collect/pay flows.
- Testing KYC integrations with 3rd parties.
- Running regression tests after API version updates.
- Validating ledger or reconciliation workflows.
- Chaos testing for transaction spikes or partner latency.
Results You Can Expect with KushoAI
- Lower cost of maintaining versioned APIs.
- Confidence during partner onboarding.
- Over 95% reduction in API testing time - From 6 to 8 hours manually to under 3 minutes with KushoAI.
- 60% reduction in maintenance workload: Self-healing test suites significantly reduce quarterly rework.
- 4x increase in coverage across functional, edge-case and security scenarios
- Visible reduction in bugs escaping to production
- More stable release cycles, which lead to fewer last-minute issues and rollbacks.
Conclusion
Testing fintech APIs doesn’t have to be complex or time-consuming. With KushoAI, you can upload your API, configure authentication, build end-to-end financial flows, and validate every critical step without writing heavy test code or managing complicated tooling.
Whether you're building UPI, card payments, KYC integrations, or reconciliation systems, KushoAI will improve coverage, reduce testing time, and ship safer fintech features.
Top comments (0)