Drippy

How to check data usage on a Mac

macOS counts the bytes, but forgets them every time you restart. Here's how to read the built-in numbers, and how to keep a history you can check against your plan.

Updated November 2026

Download for macOSPricing

This is Drippy, with made-up usage. Click around: the switches and rules work.

Activity Monitor

  1. Open Activity MonitorApplications › Utilities, or Spotlight.
  2. Click the Network tabThe bottom shows Data received and Data sent since the Mac last started.
  3. Sort by Rcvd BytesShows which processes downloaded the most since they launched.

The totals reset at every restart, and per-app numbers reset when an app quits. There's no daily or monthly view.

Terminal: nettop

Prints one sample of bytes in and out per process. Leave off -L 1 for a live view. Like Activity Monitor, it only knows about processes that are still running.

nettop -P -L 1 -J bytes_in,bytes_out

Per network interface

en0 is usually Wi-Fi. Ibytes and Obytes are totals since startup.

netstat -ib | grep -E 'Name|en0'

Keep a history with Drippy

Drippy records usage continuously and keeps it: today, this week and this month, by app and by network. Set your plan's cap and reset day, and it warns you before you go over. It shows live speeds in the menu bar too.

Questions

Does macOS have a built-in data usage tracker?

Only since-startup totals in Activity Monitor's Network tab. It doesn't keep daily or monthly history.

Why doesn't my Mac's data usage match my ISP?

Your ISP counts every device on the connection and protocol overhead. Your Mac only counts itself.

Does Drippy send my usage anywhere?

No. Usage stays on your Mac. Drippy goes online only for speed tests, your public IP and its license check.

Download Drippy

Download for macOS