Bandwidth by app

See which app is using your bandwidth.

Live upload and download for every app on your Mac, right in the menu bar. Catch the backup choking your call, the updater eating your hotspot, or the app phoning home at 3 a.m. Free.

Download for Mac ↓

$ brew install seifip/kilobat/kilobat

Free forever
Pro $19 once
14-day refunds
macOS 14+
Open-source CLI

Free

Safari3.2 MB/s824 MB

Cloud backup2.1 MB/s240 MB

Night Drive186 KB/s312 MB

Kilobat12 KB/s14 MB

Terminal

# Live, in your terminal
$ kilobat status --watch

Sound familiar?

“Something is uploading and I don’t know what.”
“Activity Monitor just says nsurlsessiond.”
“Which app used 40 GB this month?”
“Why is my Mac talking to that country?”

Better than Activity Monitor’s Network tab.

Activity Monitor answers “which process”. Kilobat answers “which app, right now, and where to”.

	Activity Monitor	Kilobat
What it shows	Processes, with totals since each one started	Apps, with helpers grouped under them, sorted by what they move right now
“nsurlsessiond”	A system process	The app it downloads for
History	None once you close it	A year by app, by hour, day, week or month (Pro)
Where it connects	Not shown	Each app’s open connections, and every connection on a globe by country (Pro)
What it should connect to	Not shown	The developer’s Internet Access Policy, when it has one
In a script	No	`kilobat status --json`, `bandwidth`, `report --csv`

App detail

Every app has an echo.

Click an app for its echo: a sentence on what it moved, a waveform that marks when you changed networks or an agent ran, which networks carried it, how today compares with its usual and its share of your Mac, live or by hour, day, week and month.

Below it: the app’s open connections, with data and country.
What the developer declares in an Internet Access Policy, and why.
Block a host for that app or every app (Pro).

Pro

🇺🇸United States48
🇩🇪Germany21
🇨🇦Canada12
🇪🇸Spain6

See where it connects. Every open connection on a globe, by the country its address belongs to. Looked up on your Mac; nothing is sent anywhere.

Totals

Numbers you can check.

The Mac’s total comes from the Wi-Fi and Ethernet counters, so it matches what actually left the machine. Local network and AirDrop transfers are shown apart and not counted, a VPN counts once, and system downloads say which app they are for.

Bytes or bits per second, as you prefer.
Compare with your router’s or provider’s figure for the same period (Pro).
Approve new apps before their first connection (Pro).

Pro

Your provider44.2 GB

Kilobat41.8 GB

Difference2.4 GB less

Recorded 668 of 720 hours · asleep, off or on other networks for the rest

Phones and TVs on the same plan
The provider’s day starts at midnight UTC

Your provider says more? Put their figure beside Kilobat’s for the same period, with the hours Kilobat recorded and the likely reasons for a difference.

CLI

Also in your terminal.

The free, open-source CLI shows the same live view with sorting, filters and search, and JSON when piped. Put it in a status bar, a cron job or an AI agent’s hands: kilobat mcp is a Model Context Protocol server with the same data.

Install with Homebrew, GPL-3.0. Every command.

Terminal

# Live per-app traffic as JSON lines
$ kilobat status --watch --json
# One app over the last week
$ kilobat bandwidth Dropbox week
# Daily totals and top apps for 30 days, as CSV
$ kilobat report --csv --days 30
# Open connections for one process
$ kilobat destinations --pid 4127

What’s free, and what Pro adds

Free, for good

Live upload and download for every app, helpers grouped
Session totals, and each app’s live echo
The open-source CLI and the MCP server

Pro, $19 once

Usage history by app, by hour, day, week and month, a year back
The connection map: every connection on a globe
Your provider’s figure beside Kilobat’s
Block apps, hosts, IPs and ranges
Ask about new apps before they connect

Pro is $19 once for two Macs, with a 7-day free trial and 14-day refunds. Free for students.

Questions

Does it need administrator rights?

No. Live per-app traffic works without root. Blocking needs the signed network filter, which you approve in macOS.

Does my traffic leave my Mac?

No. Kilobat reads counters on your Mac; history and rules stay local. Countries are looked up on your Mac too. There is no account or telemetry.

Why does it differ from my router’s number?

The router counts every device and both directions, and its day may start at a different hour. Kilobat counts this Mac, from its own interface counters. With Pro, put the router’s figure beside Kilobat’s for the same period and see the hours recorded and the likely reasons.

Is it free?

Live per-app traffic, totals and the CLI are free. History, the connection map, blocking and the comparison with your provider are part of Pro, $19 once, with a 7-day free trial.

See it as it happens.