diff --git a/include/mockturtle/algorithms/lut_mapper.hpp b/include/mockturtle/algorithms/lut_mapper.hpp
index f1be98aa7..fba44e4a1 100644
--- a/include/mockturtle/algorithms/lut_mapper.hpp
+++ b/include/mockturtle/algorithms/lut_mapper.hpp
@@ -1009,7 +1009,7 @@ class lut_map_impl
       if ( ps.required_delay < delay )
       {
         if ( !ps.area_oriented_mapping && iteration == 1 )
-          std::cerr << fmt::format( "[i] MAP WARNING: cannot meet the target required time of {:.2f}", ps.required_delay ) << std::endl;
+          std::cerr << fmt::format( "[i] MAP WARNING: cannot meet the target required time of {}", ps.required_delay ) << std::endl;
       }
       else
       {
@@ -1122,7 +1122,7 @@ class lut_map_impl
       if ( ps.required_delay < delay )
       {
         if ( !ps.area_oriented_mapping && iteration == 1 )
-          std::cerr << fmt::format( "[i] MAP WARNING: cannot meet the target required time of {:.2f}", ps.required_delay ) << std::endl;
+          std::cerr << fmt::format( "[i] MAP WARNING: cannot meet the target required time of {}", ps.required_delay ) << std::endl;
       }
       else
       {