diff --git a/src/app/tape/tmainwindow.cpp b/src/app/tape/tmainwindow.cpp
index ed2b7a184..f5f41da63 100644
--- a/src/app/tape/tmainwindow.cpp
+++ b/src/app/tape/tmainwindow.cpp
@@ -2670,7 +2670,7 @@ bool TMainWindow::EvalFormula(const QString &formula, bool fromUser, VContainer
             if (qIsInf(result) || qIsNaN(result))
             {
                 label->setText(tr("Error") + " (" + postfix + ").");
-                label->setToolTip(tr("Invalid value"));
+                label->setToolTip(tr("Invalid result. Value is infinite or NaN. Please, check your calculations."));
                 return false;
             }
 
diff --git a/src/app/valentina/dialogs/dialogincrements.cpp b/src/app/valentina/dialogs/dialogincrements.cpp
index f174a7563..ef9ae5920 100644
--- a/src/app/valentina/dialogs/dialogincrements.cpp
+++ b/src/app/valentina/dialogs/dialogincrements.cpp
@@ -343,7 +343,7 @@ bool DialogIncrements::EvalIncrementFormula(const QString &formula, bool fromUse
             if (qIsInf(result) || qIsNaN(result))
             {
                 label->setText(tr("Error") + " (" + postfix + ").");
-                label->setToolTip(tr("Invalid value"));
+                label->setToolTip(tr("Invalid result. Value is infinite or NaN. Please, check your calculations."));
                 return false;
             }
 
diff --git a/src/libs/vtools/dialogs/tools/dialogtool.cpp b/src/libs/vtools/dialogs/tools/dialogtool.cpp
index 87eb81526..3d99e37ea 100644
--- a/src/libs/vtools/dialogs/tools/dialogtool.cpp
+++ b/src/libs/vtools/dialogs/tools/dialogtool.cpp
@@ -773,7 +773,7 @@ qreal DialogTool::Eval(const QString &text, bool &flag, QLabel *label, const QSt
                 flag = false;
                 ChangeColor(labelEditFormula, Qt::red);
                 label->setText(tr("Error") + " (" + postfix + ")");
-                label->setToolTip(tr("Invalid value"));
+                label->setToolTip(tr("Invalid result. Value is infinite or NaN. Please, check your calculations."));
             }
             else
             {