diff --git a/src/grib_dumper_class_json.c b/src/grib_dumper_class_json.c
index a1e0b1e56..a63c24eaf 100644
--- a/src/grib_dumper_class_json.c
+++ b/src/grib_dumper_class_json.c
@@ -116,6 +116,7 @@ static void dump_values(grib_dumper* d,grib_accessor* a)
   long more=0;
   long count=0;
   int mydepth=depth+2;
+    double missing_value = 9999;
 
   count=grib_value_count(a);
   size=count;
@@ -145,12 +146,20 @@ static void dump_values(grib_dumper* d,grib_accessor* a)
     fprintf(self->dumper.out,"%-*s",mydepth," ");
     fprintf(self->dumper.out,"\"%s\" : [ ",a->name);
     tab=lens+mydepth+7;
-    for (i=0;i<size-1;i++) {
+
+        err = grib_get_double(a->parent->h, "missingValue", &missing_value);
+        for (i=0; i<size-1; ++i) {
         if (count>cols || i==0) {fprintf(self->dumper.out,"\n%-*s",tab," ");count=0;}
+            if (values[i] == missing_value)
+                fprintf(self->dumper.out, "%s, ", "null");
+            else
         fprintf(self->dumper.out,"%g, ",values[i]);
         count++;
     }
     if (count>cols) fprintf(self->dumper.out,"\n%-*s",tab," ");
+        if (values[i] == missing_value)
+            fprintf(self->dumper.out, "%s ","null");
+        else
     fprintf(self->dumper.out,"%g ",values[i]);
     if (more)
       fprintf(self->dumper.out,"\n%-*s... %ld more values",tab," ",more);
@@ -316,4 +325,3 @@ static void dump_section(grib_dumper* d,grib_accessor* a,grib_block_of_accessors
     grib_dump_accessors_block(d,block);
   }
 }
-
diff --git a/tools/grib_dump.c b/tools/grib_dump.c
index 4658eb2d8..cdcbfb099 100644
--- a/tools/grib_dump.c
+++ b/tools/grib_dump.c
@@ -102,7 +102,8 @@ int grib_tool_init(grib_runtime_options* options) {
 	if (grib_options_on("H"))
 		options->dump_flags |= GRIB_DUMP_FLAG_HEXADECIMAL;
 
-	if (grib_options_on("d"))
+    /* In JSON mode we want to print all data values */
+    if ( grib_options_on("d") || grib_options_on("j") )
 		options->dump_flags |= GRIB_DUMP_FLAG_ALL_DATA;
 
 	return 0;