diff --git a/locust/web.py b/locust/web.py
index 898e0667f8..dc219362c6 100644
--- a/locust/web.py
+++ b/locust/web.py
@@ -211,11 +211,14 @@ def swarm() -> Response:
             for key, value in request.form.items():
                 if key == "user_count":  # if we just renamed this field to "users" we wouldn't need this
                     user_count = int(value)
+                    parsed_options_dict["users"] = user_count
                 elif key == "spawn_rate":
                     spawn_rate = float(value)
+                    parsed_options_dict[key] = spawn_rate
                 elif key == "host":
                     # Replace < > to guard against XSS
                     environment.host = str(request.form["host"]).replace("<", "").replace(">", "")
+                    parsed_options_dict[key] = environment.host
                 elif key == "user_classes":
                     # Set environment.parsed_options.user_classes to the selected user_classes
                     parsed_options_dict[key] = request.form.getlist("user_classes")
@@ -224,6 +227,7 @@ def swarm() -> Response:
                         continue
                     try:
                         run_time = parse_timespan(value)
+                        parsed_options_dict[key] = run_time
                     except ValueError:
                         err_msg = "Valid run_time formats are : 20, 20s, 3m, 2h, 1h20m, 3h30m10s, etc."
                         logger.error(err_msg)