1. A system for verifying an unverified token received from a client device, the system comprising: a front-end website that receives the unverified token from a client device; a network interface that accesses one or more external data stores to receive a plurality of data vectors from the one or more external data stores, wherein the plurality of data vectors are associated with a user of the client device; one or more processors; and one or more memory devices comprising instructions that, when executed by the one or more processors, cause the one or more processors to perform operations comprising: filtering data vectors from the plurality of data vectors that are not input data vectors; grouping data vectors from the plurality of data vectors into a first one or more groups based at least in part on a text field in each of the plurality of data vectors; selecting a second one or more groups from the first one or more groups, wherein each of the second one or more groups comprises data vectors with a similar value field; selecting a third one or more groups from the second one or more groups, wherein each of the third one or more groups comprises data vectors with a similar input interval; for each of the third one or more groups, determining a group value based at least in part on the value fields and input intervals; calculating an estimated token based at least in part on the group values for each of the third one or more groups; and determining whether the unverified token can be verified by determining whether the estimated token is within a threshold amount of the unverified token.