Child support calculator
Estimating the child’s appropriate support
This calculator is provided without warranty and does not replace legal advice. The data you enter is not sent to the firm: it stays in your browser, on this device, until you erase it with the “Reset” button.
This tool estimates the child support due for one or more children, using the extended subsistence minimum method with distribution of the surplus (two-step method).
Fill in each child’s budget and each parent’s income and expenses, then the settings of the method (care, surplus, tax share): the summary shows each parent’s share and the monthly support due. To understand how the cost is split between the parents, see the child maintenance distribution matrix (in French).
Last updated: 26 September 2026