Throttle bandwidth for one app on your Mac

Per-app network throttling on Mac

1. Click the Lagsmith menu bar icon and pick a running app.
2. Choose a preset (Edge, 3G, DSL, LTE, WiFi, Very Bad Network) or set custom download and upload bandwidth, latency, jitter and packet loss.
3. Optionally limit the rule to some hosts, or to everything except one.

Only that app is affected. Save your settings as a custom preset to reuse them.

See what the app does on the network

For Mac apps, Lagsmith shows connections, DNS lookups and TLS details, so you can see what slowed down and what failed. Everything stays on your Mac.

Break it, too

Put the app in Airplane Mode, refuse connections, time out requests or drop connections after a few seconds. Failure modes.

Frequently asked questions

Can macOS limit bandwidth for one app?

Not with built-in settings. Network Link Conditioner limits the whole Mac. Lagsmith limits bandwidth per app.

Which apps can I throttle?

Any running Mac app, and apps in a booted iOS Simulator.

Can I limit upload and download separately?

Yes. Set download and upload bandwidth, latency, jitter and packet loss separately, and save them as your own presets.

Can I see what the app is connecting to?

Yes. For Mac apps Lagsmith shows connections, DNS lookups and TLS details.