diff --git a/src/rest/api/api_printer.lua b/src/rest/api/api_printer.lua
index 5bf04bc..04b08ce 100644
--- a/src/rest/api/api_printer.lua
+++ b/src/rest/api/api_printer.lua
@@ -203,6 +203,12 @@ function M.fetch_POST(request, response)
 		return
 	end
 
+	local state = printer:getState()
+	if state ~= "idle" then
+		response:setError("printer is not idle")
+		return
+	end
+
 
 	log:verbose(MOD_ABBR, "  clearing all gcode for " .. printer:getId())
 	response:addData('gcode_clear',true)