Abstract Adaptive e-learning is becoming increasingly popular as a tool to help learners with dyslexia. It provides more customized learning experiences based on the learners’ characteristics. Each learner with dyslexia has unique characteristics for which material should ideally be suitably tailored. However, adaptation to the characteristics of learners with dyslexia—in particular, their dyslexia type and reading skill level—is limited. By examining the learning effectiveness of adaptation of learning material based on the learner’s type of dyslexia and reading skill, this study fills a knowledge vacuum in this under-researched area. An empirical evaluation through a controlled experiment with 47 Arabic subjects has been undertaken and assessed using the following metrics: learning gain and learner satisfaction. The findings reveal that adapting learning material to the combination of dyslexia type and reading skill level yields significantly better short- and long-term learning gains and improves the learners’ satisfaction compared to non-adapted material. There is evidence that this benefit also extends to how well learners read unseen material. This paper also discusses implications and important avenues for future research and practice related to how adaptation influences learners with dyslexia.