diff --git a/include/common/stringTools.h b/include/common/stringTools.h
index 1c8a29bf5..ad04dc1a2 100644
--- a/include/common/stringTools.h
+++ b/include/common/stringTools.h
@@ -71,5 +71,13 @@ std::string to_string(T value)
     oss << value;
     return oss.str();
 }
+
+template<typename T>
+T extractFromString(const std::string& str) {
+    std::istringstream iss(str);
+    T ret;
+    iss >> ret;
+    return ret;
+}
 } //namespace kiwix
 #endif
diff --git a/src/downloader.cpp b/src/downloader.cpp
index 2f9a70cd1..778ad3fb8 100644
--- a/src/downloader.cpp
+++ b/src/downloader.cpp
@@ -72,12 +72,12 @@ void Download::updateStatus(bool follow)
     } catch (InvalidRPCNode& e) { }
   }
   m_status = status;
-  m_totalLength = structNode.getMember("totalLength").getValue().getAsI();
-  m_completedLength = structNode.getMember("completedLength").getValue().getAsI();
-  m_downloadSpeed = structNode.getMember("downloadSpeed").getValue().getAsI();
+  m_totalLength = extractFromString<uint64_t>(structNode.getMember("totalLength").getValue().getAsS());
+  m_completedLength = extractFromString<uint64_t>(structNode.getMember("completedLength").getValue().getAsS());
+  m_downloadSpeed = extractFromString<uint64_t>(structNode.getMember("downloadSpeed").getValue().getAsS());
   try {
     auto verifiedLengthValue = structNode.getMember("verifiedLength").getValue();
-    m_verifiedLength = verifiedLengthValue.getAsI();
+    m_verifiedLength = extractFromString<uint64_t>(verifiedLengthValue.getAsS());
   } catch (InvalidRPCNode& e) { m_verifiedLength = 0; }
   auto filesMember = structNode.getMember("files");
   auto fileStruct = filesMember.getValue().getArray().getValue(0).getStruct();