Background: Rounded Shoulder Posture (RSP) and Forward Head Posture (FHP) often result from prolonged digital device use, leading to muscle imbalance, pain, and functional limits. Growing demand for postural correction highlights the need for effective exercise approaches. Objectives: This study compared strengthening, self-stretching, and mixed exercises on acromion height, craniovertebral angle, and muscle tone in adults with FHP and RSP. Design: Randomized controlled pretest-post test trial over four weeks. Methods: Thirty university students (acromion height ≥2.5 cm, craniovertebral angle ≤53°) were randomly assigned to strengthening (n=6), self-stretching (n=9), or mixed exercise (n=9) groups. Participants exercised three times weekly for four weeks. Pre- and post-tests measured acromion height, craniovertebral angle, and muscle tone of the pectoralis major, upper trapezius, and sternocleidomastoid using MyotonPro®. Data were analyzed with Wilcoxon signed ranks, Kruskal-Wallis, and repeated measures ANOVA (P<.05). Results: All groups significantly improved acromion height and craniovertebral angle (P<.05) without intergroup differences. Significant tone change appeared only in the upper trapezius (P<.05), with the mixed group showing the largest improvement. Conclusion: All exercises improved posture in adults with FHP and RSP. Mixed exercise yielded the greatest reduction in upper trapezius tone, suggesting a multimodal approach may be most effective.