A computer-implemented method for confirming and for checking a digital identity of a user , wherein the method is performed by an ID provider computer system and a service computer system , wherein the method comprises: - automatically calculating trust levels (198, 414, L1-L5) for attribute values (190, V1, V2) of attributes (412, A1, A2) by the ID provider computer system with the aid of a first function , wherein the first function calculates the trust levels attribute-independently, wherein the digital identity of the user includes a plurality of the attribute values, wherein the trust level specifies a degree of reliability of the assignment of each attribute value to the user and/or the degree of reliability of the correctness of the attribute value; - automatically executing a plurality of second functions (193.1-193.4) by the ID provider computer system, wherein each of the second functions is specifically assigned to one or more of the attributes, wherein the execution of the second functions in each case causes a recalculation of the trust levels of the attribute values of those attributes to which the second function is assigned; - receiving a request to confirm the digital identity of the user, wherein the request is received by the ID provider computer system from the service computer system via a network , wherein the request contains a plurality of the attributes (A1, A2); - sending a response from the ID provider computer system to the service computer system via the network, wherein the response for a plurality of the attributes of the request in each case includes at least one attribute value (V1, V2) associated with the user and the trust level (L1-L4) assigned to this attribute value and recalculated by means of one of the second functions, wherein the trust levels are assigned to their corresponding attribute values as meta-information; - checking the digital identity of the user by the service computer system by automatic analysis both of the attribute values contained in the response and the trust levels assigned to said attribute values. - automatically calculating trust levels (198, 414, L1-L5) for attribute values (190, V1, V2) of attributes (412, A1, A2) by the ID provider computer system with the aid of a first function , wherein the first function calculates the trust levels attribute-independently, wherein the digital identity of the user includes a plurality of the attribute values, wherein the trust level specifies a degree of reliability of the assignment of each attribute value to the user and/or the degree of reliability of the correctness of the attribute value; - automatically executing a plurality of second functions (193.1-193.4) by the ID provider computer system, wherein each of the second functions is specifically assigned to one or more of the attributes, wherein the execution of the second functions in each case causes a recalculation of the trust levels of the attribute values of those attributes to which the second function is assigned; - receiving a request to confirm the digital identity of the user, wherein the request is received by the ID provider computer system from the service computer system via a network , wherein the request contains a plurality of the attributes (A1, A2); - sending a response from the ID provider computer system to the service computer system via the network, wherein the response for a plurality of the attributes of the request in each case includes at least one attribute value (V1, V2) associated with the user and the trust level (L1-L4) assigned to this attribute value and recalculated by means of one of the second functions, wherein the trust levels are assigned to their corresponding attribute values as meta-information; - checking the digital identity of the user by the service computer system by automatic analysis both of the attribute values contained in the response and the trust levels assigned to said attribute values. <EOS>