[header] How to build calf muscle without equipment [title] Do double-leg calf raises. [step] This is a classic exercise for toning and strengthening the calf muscles. This workout utilizes your own body weight instead of a weight machine to help build muscle mass. 
It strengthens both the gastrocnemius and soleus muscles. To start off, you will need to stand near a wall to balance yourself, if needed, and your feet should be hip-width apart with your ankles, knees and hips vertically aligned.