diff --git a/src/json.hpp b/src/json.hpp
index 92b913a84..d73abe0cc 100644
--- a/src/json.hpp
+++ b/src/json.hpp
@@ -56,12 +56,12 @@ SOFTWARE.
 // exclude unsupported compilers
 #if defined(__clang__)
     #define CLANG_VERSION (__clang_major__ * 10000 + __clang_minor__ * 100 + __clang_patchlevel__)
-    #if CLANG_VERSION < 34000
+    #if CLANG_VERSION < 30400
         #error "unsupported Clang version - see https://github.com/nlohmann/json#supported-compilers"
     #endif
 #elif defined(__GNUC__)
     #define GCC_VERSION (__GNUC__ * 10000 + __GNUC_MINOR__ * 100 + __GNUC_PATCHLEVEL__)
-    #if GCC_VERSION < 49000
+    #if GCC_VERSION < 40900
         #error "unsupported GCC version - see https://github.com/nlohmann/json#supported-compilers"
     #endif
 #endif
diff --git a/src/json.hpp.re2c b/src/json.hpp.re2c
index cc4df5de2..2d5732584 100644
--- a/src/json.hpp.re2c
+++ b/src/json.hpp.re2c
@@ -56,12 +56,12 @@ SOFTWARE.
 // exclude unsupported compilers
 #if defined(__clang__)
     #define CLANG_VERSION (__clang_major__ * 10000 + __clang_minor__ * 100 + __clang_patchlevel__)
-    #if CLANG_VERSION < 34000
+    #if CLANG_VERSION < 30400
         #error "unsupported Clang version - see https://github.com/nlohmann/json#supported-compilers"
     #endif
 #elif defined(__GNUC__)
     #define GCC_VERSION (__GNUC__ * 10000 + __GNUC_MINOR__ * 100 + __GNUC_PATCHLEVEL__)
-    #if GCC_VERSION < 49000
+    #if GCC_VERSION < 40900
         #error "unsupported GCC version - see https://github.com/nlohmann/json#supported-compilers"
     #endif
 #endif