Upper extremity (UE) vascularized composite allotransplantation (VCA; hand transplantation) is a reconstructive treatment option for patients with UE loss. Approximately 37 UE VCAs have been performed in the United States to date; thus, little is known about long-term psychosocial outcomes and whether the benefits outweigh the risks. To make an informed treatment decision, patients must understand the procedure, risks, and potential benefits of UE VCA. However, few educational resources are publicly available providing unbiased, comprehensive information about UE VCA. This paper described the development of a neutral, and accessible, educational website supporting informed decision-making about UE VCA as a treatment option for individuals with UE amputations. Website content development was informed by 9 focus groups conducted with individuals with UE amputations at 3 study sites. After initial website development, we conducted usability testing to identify ways to improve navigability, design, content, comprehension, and cultural sensitivity. Participants were administered the After-Scenario Questionnaire to assess user performance after completing navigational tasks, System Usability Scale to measure the perceived usability of the website, and Net Promoter Score to measure user satisfaction. Quantitative data were analyzed using descriptive statistics. Qualitative data were analyzed using rapid thematic analysis. A total of 44 individuals with UE amputations participated in focus groups (n=37, 84%) and usability testing (n=14, 32%). Most participants in the focus groups and usability testing were male (24/37, 65% and 11/14, 79%, respectively) and White (27/37, 73% and 9/14, 64%, respectively), had unilateral limb loss (22/37, 59% and 12/14, 86%, respectively), and had mean ages of 48 (SD 9.2) and 50 (SD 12.0) years, respectively. Focus group results are organized into accessibility, website design, website development, website tone and values, sitemap, terminology, images and videos, and tables and graphics. Usability testing revealed that participants had a positive impression of the website. The mean After-Scenario Questionnaire score of 1.3 to 2.3 across task scenarios indicated high satisfaction with website usability, the mean System Usability Scale score of 88.9 indicated user satisfaction with website usability, and the mean Net Promoter Score of 9.6 indicated that users were enthusiastic and would likely refer individuals to the website. The findings suggest that our educational website, Within Reach, provides neutral, patient-centered information and may be a useful resource about UE VCA for individuals with UE amputations, their families, and health care professionals. Health care professionals may inform UE VCA candidates about Within Reach to supplement current VCA education processes. Within Reach serves as a resource about treatment options for patients preparing for scheduled or recovering from traumatic UE amputations. Future research should assess whether Within Reach improves knowledge about UE VCA and enhances informed decision-making about UE VCA as a treatment option.