diff --git a/src/libqof/qof/qofint128.cpp b/src/libqof/qof/qofint128.cpp
index 8cc05806f4..02e9c2681b 100644
--- a/src/libqof/qof/qofint128.cpp
+++ b/src/libqof/qof/qofint128.cpp
@@ -64,6 +64,14 @@ QofInt128::QofInt128 (int64_t upper, int64_t lower, unsigned char flags) :
     m_flags {flags}, m_hi {upper},
     m_lo {lower} {}
 
+QofInt128&
+QofInt128::zero () noexcept
+{
+    m_flags = 0;
+    m_lo = m_hi = UINT64_C(0);
+    return *this;
+}
+
 QofInt128::operator int64_t() const
 {
     if ((m_flags & neg) && isBig())
@@ -138,6 +146,16 @@ QofInt128::isZero() const noexcept
     return ((m_flags & (overflow | NaN)) == 0 &&  m_hi == 0 && m_lo == 0);
 }
 
+QofInt128
+QofInt128::abs() const noexcept
+{
+    if (isNeg())
+        return operator-();
+
+    return *this;
+}
+
+
 QofInt128
 QofInt128::operator-() const noexcept
 {
diff --git a/src/libqof/qof/qofint128.hpp b/src/libqof/qof/qofint128.hpp
index 6b365c51ff..3abff6480c 100644
--- a/src/libqof/qof/qofint128.hpp
+++ b/src/libqof/qof/qofint128.hpp
@@ -42,6 +42,7 @@
  * on an overflowed or NaN QofInt128 will yield an overflowed or NaN
  * result, so calling routines need not check until the end of a
  * chained calculation.
+ * QofInt128 uses implicit copy and move constructors and implicit destructor.
  */
 class QofInt128
 {
@@ -75,6 +76,15 @@ enum // Values for m_flags
  */
     QofInt128 (int64_t upper, int64_t lower, unsigned char flags = '\0');
     QofInt128 (uint64_t upper, uint64_t lower, unsigned char flags = '\0');
+
+/**
+ * Clear the object.
+ *
+ * Sets all member variables to zero.
+ * @return A reference to the object for chaining.
+ */
+    QofInt128& zero() noexcept;
+
 /**
  * Compare function.
  *
@@ -90,7 +100,7 @@ enum // Values for m_flags
  */
     QofInt128 gcd (const QofInt128& b) const noexcept;
 /**
- * Computes the Least Common Multiple between the object and paramter
+ * Computes the Least Common Multiple between the object and parameter
  *
  * @return A QofInt128 having the LCM.
  */
@@ -152,6 +162,7 @@ enum // Values for m_flags
  */
     char* asCharBufR(char* buf) const noexcept;
 
+    QofInt128 abs() const noexcept;
 
     QofInt128 operator-() const noexcept;
     explicit operator bool() const noexcept;