A solitonic model of the early universe is introduced by employing the Double-Sine–Gordon (DSG) potential. The model predicts the appropriate number of e-foldings (𝑁𝑒) required for favored inflation and is an advantage for the model in addressing the flatness, horizon, and magnetic monopole problems. Compatibility of the model with observations, including the Planck 2018 data (Akrami et al., 2020) and the Planck 2018 data+BK18+BAO (Ade et al., 2021) paves the way to estimate the model’s free parameters. The results generate acceptable and proper values for the spectral index (𝑛𝑠) and the tensor-to-scalar ratio (𝑟) in agreement with the Planck 2018 data (Akrami et al., 2020) and the Planck 2018 data+BK18+BAO (Ade et al., 2021). Correspondingly, a consistent description of the reheating era is obtained, yielding positive reheating number of e-foldings (𝑁reh) and reheating final temperature (𝑇reh) from 10−2 GeV to 1016 GeV. The inflationary trans-Planckian constraint is also concurrently addressed. Overall, the model seems viable at the inflationary and reheating eras.
