Looking for logging into the Authorize Net Test Api Id site and are not getting the correct working link for it? In such a case, you can use the links given here by searching your desired login page in the search box. If the page is present on our website then you will get all the links related to the Authorize Net Test Api Id site. After that you can login as usual with your login credentials.
https://community.developer.authorize.net/t5/Integration-and-Testing/How-do-I-get-testing-API-Login-ID-and-Transaction-key-to-be/td-p/60033
https://support.authorize.net/s/article/How-do-I-obtain-my-API-Login-ID-and-Transaction-Key
https://developer.authorize.net/hello_world/sandbox/
https://developer.authorize.net/hello_world/testing_guide/
http://wp-events-plugin.com/documentation/event-bookings-auhtorize-net-sandbox/
https://support.teamsideline.com/hc/en-us/articles/201151957-Authorize-net-API-Login-ID-and-Transaction-Key-In-order-to-connect-a-website-to-the-payment-gateway
https://support.checkfront.com/hc/en-us/articles/115004505294-Payment-Gateways-Authorize-net
https://help.shopify.com/en/manual/payments/third-party-providers/set-up-authorize-net
http://helpcenter.volusion.com/run-your-business/other/how-to-set-up-authorizenet
https://docs.woocommerce.com/document/authorize-net-aim/
https://guides.spreecommerce.org/developer/gateway_specific_information.html
https://stackoverflow.com/questions/9206438/gateway-error-testmode-the-merchant-login-id-or-password-is-invalid-or-the-a
https://givewp.com/documentation/add-ons/authorize-net-gateway/testing-authorize-net/