diff --git a/src/locale/messages.en.json b/src/locale/messages.en.json
index 270145ca455df9af255a7770070d0cad86885a9c..b6db3ee3226f5c823c7a3251e76536054c448cb6 100644
--- a/src/locale/messages.en.json
+++ b/src/locale/messages.en.json
@@ -7,7 +7,7 @@
     "WARNING_ERRORS_ABSTRACT": "%nb% errors occurred during calculation",
     "ERROR_BIEF_Z1_CALC_FAILED": "Unable to calculate upstream elevation (calculation interrupted before upstream)",
     "ERROR_BIEF_Z2_CALC_FAILED": "Unable to calculate downstream elevation (calculation interrupted before downstream)",
-    "ERROR_DICHO_CONVERGE": "Dichotomy could not converge",
+    "ERROR_DICHO_CONVERGE": "Dichotomy could not converge. Last approximation: %lastApproximation%",
     "ERROR_DICHO_FUNCTION_VARIATION": "unable to determinate function direction of variation",
     "ERROR_DICHO_INIT_DOMAIN": "Dichotomy: target %targetSymbol%=%targetValue% does not exist for variable %variableSymbol% valued in interval %variableInterval%",
     "ERROR_DICHO_INVALID_STEP_GROWTH": "Dichotomy (initial interval search): invalid null step growth",
diff --git a/src/locale/messages.fr.json b/src/locale/messages.fr.json
index e04f71c079860fbb122c1d029cd8260a8d9251d4..f7dd7975fd553ea703cb40945bf09ca14980a8a8 100644
--- a/src/locale/messages.fr.json
+++ b/src/locale/messages.fr.json
@@ -7,7 +7,7 @@
     "WARNING_ERRORS_ABSTRACT": "%nb% erreurs rencontrées lors du calcul",
     "ERROR_BIEF_Z1_CALC_FAILED": "Impossible de calculer la cote amont (calcul interrompu avant l'amont)",
     "ERROR_BIEF_Z2_CALC_FAILED": "Impossible de calculer la cote aval (calcul interrompu avant l'aval)",
-    "ERROR_DICHO_CONVERGE": "La dichotomie n'a pas pu converger",
+    "ERROR_DICHO_CONVERGE": "La dichotomie n'a pas pu converger. Dernière approximation: %lastApproximation%",
     "ERROR_DICHO_FUNCTION_VARIATION": "Dichotomie : impossible de determiner le sens de  variation de la fonction",
     "ERROR_DICHO_INIT_DOMAIN": "Dichotomie : la valeur cible %targetSymbol%=%targetValue% n'existe pas pour la variable %variableSymbol% prise dans l'intervalle %variableInterval%",
     "ERROR_DICHO_INVALID_STEP_GROWTH": "Dichotomie : l'augmentation du pas pour la recherche de l'intervalle de départ est incorrecte (=0)",