**Random.org implementation for Qualtrics** The purpose of this document is to explain how JavaScript can be employed to assign random numbers to survey participants through RANDOM.ORG in the survey software Qualtrics. ---------- **Purpose:** Assigning random numbers to participants Most computer programs that generate random numbers only exhibit pseudo-randomness. That is, these numbers are generated by following a mathematical algorithm with predictable rules and results. These algorithms must use a numerical starting point (a seed) to initiate the number generation. In the pseudo-random generator used by Qualtrics, the time at which the participant enters the screen with the randomizer serves as the starting seed. This means that two participants entering the screen at the same time will be assigned to the same condition (or whatever the randomizer is set to randomize). In contrast, RANDOM.ORG offers “true” random numbers based on atmospheric noise. This offers a greater level of randomness, as it is not in any way contingent upon the actions of the survey participants or any other predictable source (for more information, see https://www.RANDOM.ORG/analysis/). RANDOM.ORG offers a service to draw random numbers for public users remotely. Thus, the JavaScript on this page is a template for submitting requests to their server. This document also contains information regarding the utilization of these true random numbers in question assignment in Qualtrics surveys. Update January 2019: Corrected JavaScript explanation to say "ajax" instead of "Ajax". Typing "Ajax" will result in a failure to execute the script. ----------------- ***Please cite this memo and JavaScript as ”Lundmark, Sebastian, and Jamie Rodriguez. 2018. Random.org implementation for Qualtrics (version April 2018). Available at https://osf.io/dg265/ ".***