If your internet plan has restricted bandwidth limit per month and the ISP is charging you per MB of data exchanged after a certain threshold is exceeded, you should install a bandwidth monitoring software that will track your internet usage behind the scenes and inform you before you hit that monthly data download/upload limit.
Not just internet usage, these programs assist you diagnose slow internet connections and whether the ISP is giving your the promised speed or not. You also get an idea about what processes or software are currently downloading or uploading data to the internet.
One of our favorite bandwidth monitor software is Net Meter - it's absolutely free, requires no configuration and it's features match that of pro software like DUMeter or Bandwidth Monitor pro.
The data is displayed inside graphs and you get an accurate idea about the true data upload speed, download speed and since how long have you been online.
Net Meter has live reports about data transferred in a day, week or the whole month. This can also be exported in text file so that you can tally the report from your ISP.
If you are on dial-up connection, we also recommend RAS Monitor - a standalone program [no installation] that you can add to your Windows startup folder. It will reside in the Windows System tray and as soon as you switch on the modem or plug in the cable connection, RAS will begin tracking your data transfer usage.
So you can finally stop worrying about exceeding your monthly internet bandwidth or those unexpected and shocking internet usage bills that sometimes made no sense to you.
NetMeter, RAS Monitor, Download Net Meter