Ages obtained with the IACgrid with diffusion vs ages from the IACgrid without diffusion (top panel). The one-to-one line is represented with the red dashed line. Ratio between the two different age computations as a function of the age from the IACgrid without diffusion (bottom panel). The red dashed line is the equality line while the gray dot-dashed lines correspond to the mean age uncertainty on stellar ages without diffusion of our sample (of 8%).