"Recalculate" in Link Detox means to re-calculate the DTOXRISK after making changes to keyword classification or link rating.
This is useful after classifying at least 80% of your keywords to help the algorithm calculate the risk of your links more accurately. It is also necessary to use the "Recalculate" function after disavowing links. Reprocessing does not cost any credits and can be done as often as needed. The "Recalculate" button will only be active if changes have been made in the report. You can also refresh the page to reload the report.