diff --git a/src/Range.cpp b/src/Range.cpp
index 8d7a6a4e..9b5f89b4 100644
--- a/src/Range.cpp
+++ b/src/Range.cpp
@@ -47,6 +47,13 @@ bool Range::operator== (const Range& other) const
          end   == other.end;
 }
 
+////////////////////////////////////////////////////////////////////////////////
+bool Range::open () const
+{
+  return start.toEpoch () > 0 &&
+         end.toEpoch () == 0;
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 bool Range::started () const
 {
diff --git a/src/Range.h b/src/Range.h
index ae640a26..d8c77c27 100644
--- a/src/Range.h
+++ b/src/Range.h
@@ -37,6 +37,7 @@ public:
   Range (const Datetime&, const Datetime&);
   bool operator== (const Range&) const;
 
+  bool open () const;
   bool started () const;
   bool ended () const;
   bool overlap (const Range&) const;