diff --git a/lib/base/json.cpp b/lib/base/json.cpp
index d9e1718c2e3..fbb59411c90 100644
--- a/lib/base/json.cpp
+++ b/lib/base/json.cpp
@@ -10,6 +10,7 @@
 #include "base/utility.hpp"
 #include <bitset>
 #include <boost/exception_ptr.hpp>
+#include <cmath>
 #include <cstdint>
 #include <json.hpp>
 #include <stack>
@@ -365,7 +366,17 @@ inline
 void JsonEncoder<prettyPrint>::NumberFloat(double value)
 {
 	BeforeItem();
-	AppendJson(value);
+
+	if (floor(value) == value) {
+		// Make sure 0.0 is serialized as 0, so Icinga DB can parse it as int.
+		if (value < 0) {
+			AppendJson((long long)value);
+		} else {
+			AppendJson((unsigned long long)value);
+		}
+	} else {
+		AppendJson(value);
+	}
 }
 
 template<bool prettyPrint>