There are many different ways to obtain Robux (for a list, click here), and you may find yourself accruing quite a bit over time. Luckily, there are several different ways to view how many you have that varies depending on your platform. Below, I shall discuss the current methods available.
Using The Website: Computers
Finding out your Robux amount on a computer is simple! All you need to do is open your favorite web browser, navigate to roblox.com, and log into your account. Once you've done this, you will see your currency levels in the upper-right of the screen. If you don't see your full values or the screen is too small to display them, you can force them to appear by simply clicking either the icon.
Using The Website: Mobile Devices
The mobile version of the website will show you your current level of Robux in different areas depending on if you are using a phone or tablet. To get to the mobile site, simply open up your device's Safari or Chrome app and navigate to roblox.com. Once there, log into your account. If you are using a phone then your current level of Robux will be displayed underneath your username on your home screen. If you are using a tablet you may tap the icon to view your Robux.
Using The Mobile App
If you are using the mobile app, you can view your number of Robux by tapping the icon in the upper-right of the screen. This will bring you to the Robux purchase page and your total should be displayed at the top.