CPU Monitoring
OtterStat provides detailed CPU monitoring with real-time usage statistics, temperature, and top processes.
Menu Bar Display
The CPU indicator supports multiple display modes (configurable in Settings → Menu Bar):
- Text Only - Usage percentage
- Graph Only - Mini live chart
- Text + Graph - Percentage with chart
- Bar - Vertical or horizontal bar
- Graph + Label - Chart with "CPU" label
CPU Popover
Click the CPU indicator to open the detailed view.
Total Usage
- Usage percentage - Overall CPU utilization
- User/System breakdown - How much CPU is used by user apps vs system processes
- Historical chart - Usage over time with 1h / 24h / 7d / 30d / All selectors
Temperature
- Real-time CPU temperature via SMC/IOKit sensors
- Supports Apple Silicon and Intel Macs
- On Apple Silicon, installing the optional privileged helper (prompted on first open) enables more accurate readings
Thermal Level
OtterStat monitors your Mac's thermal state:
- Normal (green) - Operating within normal temperature range
- Warm (yellow) - Temperature is elevated
- Hot (orange) - Temperature is high, may throttle
- Critical (red) - Thermal throttling active
You can configure a Thermal State Alert in Settings to receive a notification when the threshold is exceeded.
Per-Core Usage
On Apple Silicon Macs, cores are displayed in two groups:
Performance Cores (P-cores)
- High-performance cores for demanding tasks
- Shown in orange
- Hover over any core bar to see the exact utilization percentage
Efficiency Cores (E-cores)
- Power-efficient cores for background tasks
- Shown in green
On Intel Macs, all cores are displayed in blue.
Diagnostics
The Diagnostics section shows Apple Silicon efficiency metrics such as target utilization data. Available on Apple Silicon only.
Top Processes
The CPU popover shows the top 5 processes consuming the most CPU, with:
- App icons resolved from app bundles
- CPU usage percentage per process
- Child processes grouped under parent apps
- Usage highlighted in red/orange for high values
Tips
- High sustained CPU usage may indicate a runaway process — check Top Processes first
- The thermal level indicator helps you understand if your Mac is running hot
- Enable the Thermal State Alert in Settings to get notified automatically