diff --git a/include/ecef-coord.hpp b/include/ecef-coord.hpp
index 4bd3cf5..2de0543 100644
--- a/include/ecef-coord.hpp
+++ b/include/ecef-coord.hpp
@@ -11,7 +11,7 @@
 
 #include <cmath>
 #include <concepts>
-#include <fmt/core.h>
+#include <fmt/format.h>
 #include <sstream>
 #include <string>
 #include <type_traits>