diff --git a/src/bin_node/node_run_command.ml b/src/bin_node/node_run_command.ml
index 47ca0a7deaa896c7c58b903b3662c6037ae6301c..9f657a6047f7370e6da1e868af7a52e4ddfcc0e8 100644
--- a/src/bin_node/node_run_command.ml
+++ b/src/bin_node/node_run_command.ml
@@ -378,6 +378,21 @@ let rpc_metrics =
     ~subsystem:"rpc"
     "calls"
 
+let rpc_output_sizes =
+  Prometheus.Gauge.v_labels
+    ~label_names:["endpoint"; "method"]
+    ~help:"RPC endpoint response body output sizes in bytes."
+    ~namespace:Tezos_version.Octez_node_version.namespace
+    ~subsystem:"rpc"
+    "calls_output_size"
+
+let rpc_ok_responses_counter =
+  Prometheus.Counter.v
+    ~help:"Total number of 200 response codes from RPC calls"
+    ~namespace:Tezos_version.Octez_node_version.namespace
+    ~subsystem:"rpc"
+    "200_status_codes"
+
 module Metrics_server = Prometheus_app.Cohttp (Cohttp_lwt_unix.Server)
 
 type port = int
@@ -451,8 +466,32 @@ let launch_rpc_server (config : Config_file.t) dir rpc_server_kind addr =
       Lwt.return (`Response response)
     else Tezos_rpc_http_server.RPC_server.resto_callback server conn req body
   in
-  let update_metrics uri meth =
-    Prometheus.Summary.(time (labels rpc_metrics [uri; meth]) Sys.time)
+  (* Update total output size *)
+  let update_output_size uri meth output_size =
+    Prometheus.Gauge.(
+      inc (labels rpc_output_sizes [uri; meth]) (Int64.to_float output_size))
+  in
+  (* Update status code metric *)
+  let update_status_code (response : Cohttp_lwt.Response.t) =
+    match response.status with
+    | `OK -> Prometheus.Counter.inc_one rpc_ok_responses_counter
+    | _ -> ()
+  in
+  let update_metrics uri meth callback =
+    let*! (response : Cohttp_lwt_unix.Server.response_action) =
+      (* Update number of operations and total time *)
+      Prometheus.Summary.(time (labels rpc_metrics [uri; meth]) Sys.time)
+        callback
+    in
+    match response with
+    | `Response (response, body) ->
+        let*! output_size, body = Cohttp_lwt.Body.length body in
+        update_output_size uri meth output_size ;
+        update_status_code response ;
+        Lwt.return (`Response (response, body))
+    | `Expert (response, _fn) as expert_response ->
+        update_status_code response ;
+        Lwt.return expert_response
   in
   let callback =
     RPC_middleware.rpc_metrics_transform_callback ~update_metrics dir callback