This application provides a JSON endpoint that will validate a provided bank account number and sort code against the Vocalink Mastercard modulus checking specification, based on the algorithms indicated in the weight table documented in section 6.1 of the specification.
- All account numbers and sort codes are considered valid unless otherwise stated
- There is no account number validation within the web service endpoint. This is outside of the scope of this application.
- Currently, only exceptions 4 and 7 are supported. Any account details requiring other exception checks will not be processed and will be considered valid.
This API endpoint is currently deployed to the following website address: http://jaywilkinson.co.uk/api/moduluscheck/
It can be tested by providing a subsequent account number and sort code. A response will be returned in JSON, in the format of a boolean to the value of true or false, depending on the result of the validation processing. For example: http://jaywilkinson.co.uk/api/moduluscheck/validateaccount?sortCode=089999&accountNumber=66374959
Please note that if a sort code or account number is outside of the range of the weight table, it will still return a value of true based on the considerations documented above.
The below table details some test accounts which were obtained from the specification
| Account Number | Sort Code | Algorithm | Valid | Test URL | Notes |
|---|---|---|---|---|---|
| 66374958 | 089999 | Modulus 10 | Yes | Test | |
| 88837491 | 107999 | Modulus 11 | Yes | Test | |
| 66374959 | 089999 | Modulus 10 | No | Test | |
| 88837493 | 107999 | Modulus 11 | No | Test | |
| 66831036 | 203099 | Modulus 11 Double Alt | No | Test | Exception 6 is not supported - returns true |
| 58716970 | 203099 | Modulus 11 Double Alt | No | Test | Exception 6 is not supported - returns true |
| 63849203 | 134020 | Modulus 11 | Yes | Test | Exception 4 |
| 99345694 | 772798 | Modulus 11 | Yes | Test | Exception 7 |
Please note that the Unit Tests included in the Core project will provide a more accurate and detailed result, and all of the above tests are covered.
For installation on a local environment for local development within IIS:
- Pull the latest release down, build and compile, restoring any Nuget packages.
- Create an IIS website, and map it to the ModulusChecker directory (as this contains the web project)
- Configure any bindings, and make any appropriate updates to the Windows Hosts file if deploying to a local development URL