local Players = game:GetService("Players")
local LocalPlayer = Players.LocalPlayer
local CoreGui = game:GetService("CoreGui")

local UPDATE_INTERVAL = 0.5
local floor = math.floor

-- pre-computed colors
local GREEN  = Color3.fromRGB(0, 255, 0)
local YELLOW = Color3.fromRGB(255, 200, 0)
local RED    = Color3.fromRGB(255, 60, 60)
local GRAY   = Color3.fromRGB(180, 180, 180)

-- destroy old instance on re-execution
local old = CoreGui:FindFirstChild("PingDisplay")
if old then old:Destroy() end

local gui = Instance.new("ScreenGui")
gui.Name = "PingDisplay"
gui.ResetOnSpawn = false
gui.IgnoreGuiInset = true
gui.ZIndexBehavior = Enum.ZIndexBehavior.Sibling
gui.Parent = CoreGui

local label = Instance.new("TextLabel")
label.Name = "PingLabel"
label.BackgroundTransparency = 1
label.AnchorPoint = Vector2.new(1, 0)
label.Position = UDim2.new(1, -8, 0, 8)
label.Size = UDim2.fromOffset(140, 20)
label.Font = Enum.Font.Gotham
label.TextSize = 14
label.TextXAlignment = Enum.TextXAlignment.Right
label.TextYAlignment = Enum.TextYAlignment.Top
label.TextColor3 = GRAY
label.TextStrokeTransparency = 0
label.Text = "Ping: -- ms"
label.Parent = gui

local function colorForPing(ms)
    if ms < 80 then
        return GREEN
    elseif ms < 160 then
        return YELLOW
    else
        return RED
    end
end

local lastMs

task.spawn(function()
    while true do
        local ping = LocalPlayer:GetNetworkPing()
        if ping and ping == ping and ping < math.huge then
            local ms = floor(ping * 1000)
            -- only write when the displayed value actually changes
            if ms ~= lastMs then
                lastMs = ms
                label.Text = "Ping: " .. ms .. " ms"
                label.TextColor3 = colorForPing(ms)
            end
        else
            if lastMs ~= nil then
                lastMs = nil
                label.Text = "Ping: --"
                label.TextColor3 = GRAY
            end
        end
        task.wait(UPDATE_INTERVAL)
    end
end)