Background: Dementia has a huge physical, psychological, social and economic impact upon caregivers, families and societies at large. There has been a growing impetus to utilize Internet interventions given the potential scalability, and presumed cost-effectiveness and accessibility. In this paper, we describe the design of a randomized controlled trial (RCT) aiming to study the impact of online self-help programs on caregivers of people with dementia in India. The experimental group will receive an interactive training and support program and the comparison group will receive an education-only e-book. It will be among the first online support intervention RCTs for a mental health condition in a lower-middle income country. Methods and design: Two hundred and eight participants are expected to be recruited via several strategies (email, Internet and social media, telephone and face-to-face) starting in the Bangalore region of India. The inclusion criteria for participation in the trial are: (1) being 18 years or older, (2) being a self-reported caregiver of a person with dementia, (3) self-report that a family member has a diagnosis of dementia (AD8 ≥ 2), and experience caregiver distress (≥ 4 on a 1-item burden scale ranging from 1 to 10 or ≥ 4 or < 20 on the Center for Epidemiologic Study-Depression (CES-D) scale (10-item) or ≥ 4 or < 15 on the Generalized Anxiety Disorder Scale (7-item). The intervention group will be offered iSupport, an online self-help training and support program, enabling a personalized education plan with a maximum of 23 lessons. These modules present a range of topics from "what is dementia?" to "dealing with challenging behaviors like aggression." The comparison group will receive an education-only e-book containing similar content. The outcomes of this trial are: caregiver burden as measured by the 22-item Zarit Burden Scale, depressive symptoms, anxiety symptoms (primary outcomes), quality of life, person-centered attitude, self-efficacy and mastery (secondary outcomes). Discussion: Based on the findings of this trial, we will examine the potential use and scale up of iSupport for caregiver distress in India. This style of online self-help programs could be expanded to other regions or countries or to other suitable caregiver groups.