Stellar mass–size relation showing the correlation of size, traced by the isophotal radius (R_25.5) with the stellar mass. The DG, ETG, and original S⁴G samples are represented with purple circles, orange stars, and blue triangles respectively. The isophotal radius axis is on a logarithmic scale. The left panel shows the size of galaxies with no correction, and the left panel shows the size of galaxies with inclination correction.