The Hubble constant (H0), which represents the expansion rate of the universe, is one of the most important cosmological parameters. The recent measurements of H0 using the distance ladder methods such as type Ia supernovae are significantly greater than the CMB measurements by Planck. The difference points to a crisis in the standard model of cosmology termed Hubble tension. In this work we compare different cosmological models, determine the Hubble constant and comment on the Hubble tension using the data from differential ages of galaxies. The data we use are free from systematic effects as the absolute age estimation of the galaxies is not needed. We apply the Bayesian approach along with the commonly used maximum likelihood method to estimate H0 and calculate the AIC scores to compare the different cosmological models. The non-flat cosmological model provides a higher value for matter density as well as the Hubble constant compared to the flat ΛCDM model. The AIC score is smaller for the flat ΛCDM cosmology compared to the non-flat model indicating the flat model a better choice. The best-fit values of H0 for both these models are 68.7 ± 3.1 km s−1 Mpc−1 and 72.2 ± 4 km s−1 Mpc−1, respectively. Our results are consistent with the CCHP measurements. However, the flat model result does not agree with the SH0ES result, while the non-flat result is inconsistent with the Planck value.