How to see data usage per app on a Mac

Updated October 23, 2026

Short answer

Open Activity Monitor → Network: each app and process has a Sent Bytes and Rcvd Bytes total since your last restart. For a live view, type nettop -P in Terminal. For daily and monthly totals on each network, use Byter alongside them.

Activity Monitor (easiest)

Open Activity Monitor and choose the Network tab.
Sort by Rcvd Bytes (downloads) or Sent Bytes (uploads).
Totals count from your last restart.

nettop in Terminal (live)

Open Terminal and type nettop -P. You’ll see a live list of processes and how much each is sending and receiving. Press q to quit.

Usage over days and months

Both tools forget everything when you restart. Byter records your total usage on each network (home Wi‑Fi, office, hotspot) by day, week, month and year. Use Activity Monitor to find which app, and Byter to see how much and where. Byter also sends a heads-up when your usage is unusually high, plus daily, weekly and monthly summaries.

Questions

Which app is using my data on Mac?

Activity Monitor → Network, sorted by Rcvd Bytes, shows the biggest users since your last restart.

Does Byter show usage per app?

Byter tracks usage per network with full history, live speed and speed tests. For a per-app breakdown, use Activity Monitor alongside it.