diff --git a/src/plugins/debugger/registerhandler.cpp b/src/plugins/debugger/registerhandler.cpp
index 16279988f70..f6482a930e1 100644
--- a/src/plugins/debugger/registerhandler.cpp
+++ b/src/plugins/debugger/registerhandler.cpp
@@ -588,7 +588,7 @@ QVariant RegisterEditItem::data(int column, int role) const
         case Qt::ToolTipRole: {
                 RegisterItem *registerItem = static_cast<RegisterItem *>(parent()->parent());
                 return RegisterHandler::tr("Edit bits %1...%2 of register %3")
-                        .arg(m_index * 8).arg(m_index * 8 + 8)
+                        .arg(m_index * 8).arg(m_index * 8 + 7)
                         .arg(QString::fromLatin1(registerItem->m_reg.name));
             }
         default: