diff --git a/apps/solver/base.de.i18n b/apps/solver/base.de.i18n
index fff3b1db9..8a0be2688 100644
--- a/apps/solver/base.de.i18n
+++ b/apps/solver/base.de.i18n
@@ -4,6 +4,7 @@ AddEquation = "Gleichung hinzuzufügen"
 ResolveEquation = "Lösen der Gleichung"
 ResolveSystem = "Lösen des Gleichungssystems"
 UseEquationModel = "Verwenden Sie einen Gleichungsmodell"
+RequireEquation = "Die Eingabe muss eine Gleichung sein"
 UndefinedEquation = "Undefinierte Gleichung"
 TooManyVariables = "Es gibt zu viele Unbekannte"
 NonLinearSystem = "Das System ist nicht linear"
diff --git a/apps/solver/base.en.i18n b/apps/solver/base.en.i18n
index 5a22550f4..0aaa4efe4 100644
--- a/apps/solver/base.en.i18n
+++ b/apps/solver/base.en.i18n
@@ -4,6 +4,7 @@ AddEquation = "Add equation"
 ResolveEquation = "Solve the equation"
 ResolveSystem = "Solve the system"
 UseEquationModel = "Use an equation template"
+RequireEquation = "The input must be an equation"
 UndefinedEquation = "Undefined equation"
 TooManyVariables = "There are too many unknowns"
 NonLinearSystem = "The system is not linear"
diff --git a/apps/solver/base.es.i18n b/apps/solver/base.es.i18n
index ec2c46ae7..7611eb06f 100644
--- a/apps/solver/base.es.i18n
+++ b/apps/solver/base.es.i18n
@@ -4,6 +4,7 @@ AddEquation = "Agregar una ecuación"
 ResolveEquation = "Resolver la ecuación"
 ResolveSystem = "Resolver el sistema"
 UseEquationModel = "Usar un modelo de ecuación"
+RequireEquation = "La entrada debe ser una ecuación"
 UndefinedEquation = "Ecuación indefinida"
 TooManyVariables = "Hay demasiadas incógnitas"
 NonLinearSystem = "El sistema no es lineal"
diff --git a/apps/solver/base.fr.i18n b/apps/solver/base.fr.i18n
index 27b8c67c5..f8d408d11 100644
--- a/apps/solver/base.fr.i18n
+++ b/apps/solver/base.fr.i18n
@@ -4,6 +4,7 @@ AddEquation = "Ajouter une équation"
 ResolveEquation = "Résoudre l'équation"
 ResolveSystem = "Résoudre le système"
 UseEquationModel = "Utiliser un modèle d'équation"
+RequireEquation = "L'entrée doit être une équation"
 UndefinedEquation = "Une equation est indéfinie"
 TooManyVariables = "Le nombre d'inconnues est trop grand"
 NonLinearSystem = "Le système n'est pas linéaire"
diff --git a/apps/solver/base.pt.i18n b/apps/solver/base.pt.i18n
index 159a152e9..96a97debf 100644
--- a/apps/solver/base.pt.i18n
+++ b/apps/solver/base.pt.i18n
@@ -4,6 +4,7 @@ AddEquation = "Adicione uma equação"
 ResolveEquation = "Resolver a equação"
 ResolveSystem = "Resolver o sistema"
 UseEquationModel = "Usar um modelo de equação"
+RequireEquation = "A entrada deve ser uma equação"
 UndefinedEquation = "Equação indefinida"
 TooManyVariables = "Existem muitas incógnitas"
 NonLinearSystem = "O sistema não é linear"
diff --git a/apps/solver/list_controller.cpp b/apps/solver/list_controller.cpp
index 063586aaa..7c238a70e 100644
--- a/apps/solver/list_controller.cpp
+++ b/apps/solver/list_controller.cpp
@@ -117,6 +117,10 @@ bool ListController::textFieldDidReceiveEvent(TextField * textField, Ion::Events
     if (!textRepresentsAnEquality(textField->text())) {
       textField->handleEvent(Ion::Events::ShiftRight);
       textField->handleEventWithText("=0");
+      if (!textRepresentsAnEquality(textField->text())) {
+        app()->displayWarning(I18n::Message::RequireEquation);
+        return true;
+      }
     }
   }
   if (Shared::TextFieldDelegate::textFieldDidReceiveEvent(textField, event)) {
@@ -132,6 +136,11 @@ bool ListController::expressionLayoutFieldDidReceiveEvent(ExpressionLayoutField
     if (!textRepresentsAnEquality(buffer)) {
       expressionLayoutField->handleEvent(Ion::Events::ShiftRight);
       expressionLayoutField->handleEventWithText("=0");
+      expressionLayoutField->writeTextInBuffer(buffer, TextField::maxBufferSize());
+      if (!textRepresentsAnEquality(buffer)) {
+        app()->displayWarning(I18n::Message::RequireEquation);
+        return true;
+      }
     }
   }
   if (Shared::ExpressionLayoutFieldDelegate::expressionLayoutFieldDidReceiveEvent(expressionLayoutField, event)) {