+12W
Charging
Adapter
94W
System
82W
Battery
+12W
SourceAC Power (MagSafe 3)
StatusCharging
SoC RangeToday: 42% — 87%
POWER ADAPTER
ConnectionMagSafe 3
Rated Power94W
Delivery24.8W
Cable quality & power flow.
Charging
Adapter powers system + charges battery
94W
Adapter
MagSafe 3
-82W
System
load
+12W
Battery
87%
Features
Power monitoring
Connections
Top processes
Battery health
Cycle count
Adapter details
Sessions
Energy by app
Lightweight
Pricing
Free
$0
Menu bar wattage
Power flow diagram
Battery info & health %
Connection detection
Power history sparkline
Time estimates
Dark & light themes
PRO
Pro
$5
one-time
Everything in Free
Per-app energy tracking
Historical charts & trends
Connected devices & USB info
Cell health & diagnostics
Session tracking
Data export (CSV)
Lifetime stats & cycle trends
Questions
Is Wattro free?
The core app is free. Wattro Pro ($5 one-time) adds per-cell voltage, resistance, and imbalance detection.
macOS says the app can't be opened
Right-click the app, choose Open, then click Open in the dialog. This is a one-time step required for apps distributed outside the App Store.
How accurate are the readings?
Wattro reads from macOS IOKit — the same data source Apple's system tools use. Readings are smoothed with an exponential moving average.
Will it drain my battery?
Under 0.5% CPU. Adaptive polling: 30s when idle, 1s only while the popover is open.
Does it phone home?
No. Zero network requests. No analytics, no telemetry. Only exception: optional Pro license verification.