diff --git a/src/include/units/pow.h b/src/include/units/bits/pow.h
similarity index 96%
rename from src/include/units/pow.h
rename to src/include/units/bits/pow.h
index 81bc9db2..c6693103 100644
--- a/src/include/units/pow.h
+++ b/src/include/units/bits/pow.h
@@ -25,7 +25,7 @@
 #include <cstdint>
 #include <cassert>
 
-namespace units {
+namespace units::detail {
 
 constexpr std::intmax_t ipow10(std::intmax_t exp)
 {
@@ -58,4 +58,4 @@ constexpr Rep fpow10(std::intmax_t exp)
   return result;
 }
 
-}  // namespace units
+}  // namespace units::detail
diff --git a/src/include/units/quantity.h b/src/include/units/quantity.h
index fce49bd4..eb38df01 100644
--- a/src/include/units/quantity.h
+++ b/src/include/units/quantity.h
@@ -25,8 +25,8 @@
 
 #include <units/bits/common_quantity.h>
 #include <units/bits/dimension_op.h>
+#include <units/bits/pow.h>
 #include <units/bits/to_string.h>
-#include <units/pow.h>
 #include <units/quantity_cast.h>
 
 #if COMP_MSVC || COMP_GCC >= 10
@@ -343,9 +343,9 @@ template<typename D1, typename U1, typename Rep1, typename D2, typename U2, type
   using common_rep = decltype(lhs.count() * rhs.count());
   const ratio r = U1::ratio * U2::ratio;
     if constexpr (treat_as_floating_point<common_rep>) {
-      return lhs.count() * rhs.count() * static_cast<common_rep>(r.num * fpow10<common_rep>(r.exp)) / static_cast<common_rep>(r.den);
+      return lhs.count() * rhs.count() * static_cast<common_rep>(r.num * detail::fpow10<common_rep>(r.exp)) / static_cast<common_rep>(r.den);
     } else {
-      return lhs.count() * rhs.count() * static_cast<common_rep>(r.num * ipow10(r.exp)) / static_cast<common_rep>(r.den);
+      return lhs.count() * rhs.count() * static_cast<common_rep>(r.num * detail::ipow10(r.exp)) / static_cast<common_rep>(r.den);
     }
 }
 
diff --git a/src/include/units/quantity_cast.h b/src/include/units/quantity_cast.h
index d741b319..79509c50 100644
--- a/src/include/units/quantity_cast.h
+++ b/src/include/units/quantity_cast.h
@@ -26,7 +26,7 @@
 #include <units/customization_points.h>
 #include <units/bits/dimension_op.h>
 #include <units/bits/external/type_traits.h>
-#include <units/pow.h>
+#include <units/bits/pow.h>
 #include <units/quantity.h>
 #include <units/quantity_point.h>
 #include <cassert>
@@ -63,13 +63,13 @@ struct quantity_cast_impl<To, CRatio, CRep, true, true, false> {
   static constexpr To cast(const Q& q)
   {
     if constexpr (treat_as_floating_point<CRep>) {
-      return To(static_cast<TYPENAME To::rep>(static_cast<CRep>(q.count()) * static_cast<CRep>(fpow10<CRep>(CRatio.exp))));
+      return To(static_cast<TYPENAME To::rep>(static_cast<CRep>(q.count()) * static_cast<CRep>(detail::fpow10<CRep>(CRatio.exp))));
     } else {
       if constexpr (CRatio.exp > 0) {
-        return To(static_cast<TYPENAME To::rep>(static_cast<CRep>(q.count()) * static_cast<CRep>(ipow10(CRatio.exp))));
+        return To(static_cast<TYPENAME To::rep>(static_cast<CRep>(q.count()) * static_cast<CRep>(detail::ipow10(CRatio.exp))));
       }
       else {
-        return To(static_cast<TYPENAME To::rep>(static_cast<CRep>(q.count()) / static_cast<CRep>(ipow10(-CRatio.exp))));
+        return To(static_cast<TYPENAME To::rep>(static_cast<CRep>(q.count()) / static_cast<CRep>(detail::ipow10(-CRatio.exp))));
       }
     }
   }
@@ -93,21 +93,21 @@ struct quantity_cast_impl<To, CRatio, CRep, false, false, false> {
   {
     if constexpr (treat_as_floating_point<CRep>) {
       return To(static_cast<TYPENAME To::rep>(static_cast<CRep>(q.count()) *
-                                     static_cast<CRep>(fpow10<CRep>(CRatio.exp)) *
+                                     static_cast<CRep>(detail::fpow10<CRep>(CRatio.exp)) *
                                      (static_cast<CRep>(CRatio.num) /
                                       static_cast<CRep>(CRatio.den))));
     } else {
       if constexpr (CRatio.exp > 0) {
         return To(static_cast<TYPENAME To::rep>(static_cast<CRep>(q.count()) *
                                       static_cast<CRep>(CRatio.num) *
-                                      static_cast<CRep>(ipow10(CRatio.exp)) /
+                                      static_cast<CRep>(detail::ipow10(CRatio.exp)) /
                                       static_cast<CRep>(CRatio.den)));
       }
       else {
         return To(static_cast<TYPENAME To::rep>(static_cast<CRep>(q.count()) *
                                       static_cast<CRep>(CRatio.num) /
                                       (static_cast<CRep>(CRatio.den) *
-                                       static_cast<CRep>(ipow10(-CRatio.exp)))));
+                                       static_cast<CRep>(detail::ipow10(-CRatio.exp)))));
       }
     }
   }
@@ -128,13 +128,13 @@ struct quantity_cast_impl<To, CRatio, CRep, true, false, false> {
   static constexpr To cast(const Q& q)
   {
     if constexpr (treat_as_floating_point<CRep>) {
-      return To(static_cast<TYPENAME To::rep>(static_cast<CRep>(q.count()) * static_cast<CRep>(fpow10<CRep>(CRatio.exp)) * (CRep{1} / static_cast<CRep>(CRatio.den))));
+      return To(static_cast<TYPENAME To::rep>(static_cast<CRep>(q.count()) * static_cast<CRep>(detail::fpow10<CRep>(CRatio.exp)) * (CRep{1} / static_cast<CRep>(CRatio.den))));
     } else {
       if constexpr (CRatio.exp > 0) {
-        return To(static_cast<TYPENAME To::rep>(static_cast<CRep>(q.count()) * static_cast<CRep>(ipow10(CRatio.exp)) / static_cast<CRep>(CRatio.den)));
+        return To(static_cast<TYPENAME To::rep>(static_cast<CRep>(q.count()) * static_cast<CRep>(detail::ipow10(CRatio.exp)) / static_cast<CRep>(CRatio.den)));
       }
       else {
-        return To(static_cast<TYPENAME To::rep>(static_cast<CRep>(q.count()) / (static_cast<CRep>(ipow10(-CRatio.exp)) * static_cast<CRep>(CRatio.den))));
+        return To(static_cast<TYPENAME To::rep>(static_cast<CRep>(q.count()) / (static_cast<CRep>(detail::ipow10(-CRatio.exp)) * static_cast<CRep>(CRatio.den))));
       }
     }
   }
@@ -155,13 +155,13 @@ struct quantity_cast_impl<To, CRatio, CRep, false, true, false> {
   static constexpr To cast(const Q& q)
   {
     if constexpr (treat_as_floating_point<CRep>) {
-      return To(static_cast<TYPENAME To::rep>(static_cast<CRep>(q.count()) * static_cast<CRep>(CRatio.num) * static_cast<CRep>(fpow10<CRep>(CRatio.exp))));
+      return To(static_cast<TYPENAME To::rep>(static_cast<CRep>(q.count()) * static_cast<CRep>(CRatio.num) * static_cast<CRep>(detail::fpow10<CRep>(CRatio.exp))));
     } else {
       if constexpr (CRatio.exp > 0) {
-        return To(static_cast<TYPENAME To::rep>(static_cast<CRep>(q.count()) * static_cast<CRep>(CRatio.num) * static_cast<CRep>(ipow10(CRatio.exp))));
+        return To(static_cast<TYPENAME To::rep>(static_cast<CRep>(q.count()) * static_cast<CRep>(CRatio.num) * static_cast<CRep>(detail::ipow10(CRatio.exp))));
       }
       else {
-        return To(static_cast<TYPENAME To::rep>(static_cast<CRep>(q.count()) * static_cast<CRep>(CRatio.num) / static_cast<CRep>(ipow10(-CRatio.exp))));
+        return To(static_cast<TYPENAME To::rep>(static_cast<CRep>(q.count()) * static_cast<CRep>(CRatio.num) / static_cast<CRep>(detail::ipow10(-CRatio.exp))));
       }
     }
   }
@@ -173,13 +173,13 @@ struct quantity_cast_impl<To, CRatio, CRep, true, true, false> {
   static constexpr To cast(const Q& q)
   {
     if constexpr (treat_as_floating_point<CRep>) {
-      return To(static_cast<TYPENAME To::rep>(q.count() * fpow10<CRep>(CRatio.exp)));
+      return To(static_cast<TYPENAME To::rep>(q.count() * detail::fpow10<CRep>(CRatio.exp)));
     } else {
       if constexpr (CRatio.exp > 0) {
-        return To(static_cast<TYPENAME To::rep>(q.count() * ipow10(CRatio.exp)));
+        return To(static_cast<TYPENAME To::rep>(q.count() * detail::ipow10(CRatio.exp)));
       }
       else {
-        return To(static_cast<TYPENAME To::rep>(q.count() / ipow10(-CRatio.exp)));
+        return To(static_cast<TYPENAME To::rep>(q.count() / detail::ipow10(-CRatio.exp)));
       }
     }
   }
@@ -200,13 +200,13 @@ struct quantity_cast_impl<To, CRatio, CRep, false, false, false> {
   static constexpr To cast(const Q& q)
   {
     if constexpr (treat_as_floating_point<CRep>) {
-      return To(static_cast<TYPENAME To::rep>(q.count() * fpow10<CRep>(CRatio.exp) * (CRatio.num / CRatio.den)));
+      return To(static_cast<TYPENAME To::rep>(q.count() * detail::fpow10<CRep>(CRatio.exp) * (CRatio.num / CRatio.den)));
     } else {
       if constexpr (CRatio.exp > 0) {
-        return To(static_cast<TYPENAME To::rep>(q.count() * CRatio.num * ipow10(CRatio.exp) / CRatio.den));
+        return To(static_cast<TYPENAME To::rep>(q.count() * CRatio.num * detail::ipow10(CRatio.exp) / CRatio.den));
       }
       else {
-        return To(static_cast<TYPENAME To::rep>(q.count()) * CRatio.num / (CRatio.den * ipow10(-CRatio.exp)));
+        return To(static_cast<TYPENAME To::rep>(q.count()) * CRatio.num / (CRatio.den * detail::ipow10(-CRatio.exp)));
       }
     }
   }
@@ -227,13 +227,13 @@ struct quantity_cast_impl<To, CRatio, CRep, true, false, false> {
   static constexpr To cast(const Q& q)
   {
     if constexpr (treat_as_floating_point<CRep>) {
-      return To(static_cast<TYPENAME To::rep>(q.count() * fpow10<CRep>(CRatio.exp) / CRatio.den));
+      return To(static_cast<TYPENAME To::rep>(q.count() * detail::fpow10<CRep>(CRatio.exp) / CRatio.den));
     } else {
       if constexpr (CRatio.exp > 0) {
-        return To(static_cast<TYPENAME To::rep>(q.count() * ipow10(CRatio.exp) / CRatio.den));
+        return To(static_cast<TYPENAME To::rep>(q.count() * detail::ipow10(CRatio.exp) / CRatio.den));
       }
       else {
-        return To(static_cast<TYPENAME To::rep>(q.count() / (ipow10(-CRatio.exp) * CRatio.den)));
+        return To(static_cast<TYPENAME To::rep>(q.count() / (detail::ipow10(-CRatio.exp) * CRatio.den)));
       }
     }
   }
@@ -254,13 +254,13 @@ struct quantity_cast_impl<To, CRatio, CRep, false, true, false> {
   static constexpr To cast(const Q& q)
   {
     if constexpr (treat_as_floating_point<CRep>) {
-      return To(static_cast<TYPENAME To::rep>(q.count() * CRatio.num * fpow10<CRep>(CRatio.exp)));
+      return To(static_cast<TYPENAME To::rep>(q.count() * CRatio.num * detail::fpow10<CRep>(CRatio.exp)));
     } else {
       if constexpr (CRatio.exp > 0) {
-        return To(static_cast<TYPENAME To::rep>(q.count() * CRatio.num * ipow10(CRatio.exp)));
+        return To(static_cast<TYPENAME To::rep>(q.count() * CRatio.num * detail::ipow10(CRatio.exp)));
       }
       else {
-        return To(static_cast<TYPENAME To::rep>(q.count() * CRatio.num / ipow10(-CRatio.exp)));
+        return To(static_cast<TYPENAME To::rep>(q.count() * CRatio.num / detail::ipow10(-CRatio.exp)));
       }
     }
   }