One of the development regions in Central Java is the Solo agglomeration. Some sectors, including the industrial sector, influence the economic growth of the Solo agglomeration. The mobility of freight transportation significantly affects economic expansion. Therefore, estimating the distribution of freight transportation while planning transportation is crucial. This study aims to estimate the distribution of freight transportation represented by the origin–destination matrix. The origin–destination matrix of freight transportation is calculated using the gravity model. The maximum entropy approach model calibrates the parameters of the Gravity Model. This freight transport modeling can be used for future transportation planning, supported by a good model validity of 0.687. The total freight movement in the Solo agglomeration in 2023 was 3784 pcu/h. As much as 70% of the movement in the Solo agglomeration region comes from movements between internal zones.