Mac: Monitor Internet Bandwidth Usage

1. To get started, download and install SurplusMeter.
2. Launch it from your Applications folder. The main interface will appear, and you’ll need to make a few adjustments before you’re done. First, select the Connection type: – as the default is PPP modem, and hopefully you have broadband via your Ethernet port or Airport wireless. Because SurplusMeter was actually created with the idea of tracking exactly how much you use the Internet, you can even set a Month starts on date (ie. the first day of your billing cycle) – since that’s how most ISP’s who limit your bandwidth will monitor it. If you don’t actually have a “set in stone” download limit, you can ignore the Download limit: setting, but you may want to make it higher than the 3GB that it defaults to. I set it to 500GB.
   
   
   
3. And once the Connection type: change is made, you’ll see your total downloads/uploads since SurplusMeter was installed. Click the green button in the upper-left corner.

4. SurplusMeter will go into ‘mini-mode’. You can also quit SurplusMeter entirely, and it will still keep track of your usage. When installed, it actually puts a small program in your start-up items, and it’s that program that really does the monitoring.

5. If you open your System Preferences, select Accounts and then when your account is highlighted, click Login Items, you’ll notice that SurplusMeterAgent has been added to your start-up items. SurplusMeterAgent is what tracks your usage.
 
6. Tip: if you do use Ethernet or Airport, and transfer files across your local network – use the Pause Monitoring button. That will stop SurplusMeter from ‘tracking’ your usage until you un-pause again (and it does track local-network traffic the same way it does Internet bandwidth, which could artificially inflate your usage stats if you don’t use the Pause button).