I’ve tested more system monitors than I care to admit, but iStat Menus from Bjango remains the gold standard. After running it on my M2 MacBook Air for several weeks, I can confirm it’s exactly what they claim: the most CPU-friendly system monitoring app on macOS.
What makes iStat Menus special is the sheer breadth of information it surfaces. In my menu bar, I’ve got real-time CPU usage showing both efficiency and performance cores separately, memory pressure with compression stats, network bandwidth graphs, disk activity, and battery time remaining. The level of detail is extraordinary - click any menu bar item and you get comprehensive dropdown menus with history graphs, per-app breakdowns, and dozens of additional metrics.
Version 7.1 (the current release) is a complete rewrite sporting an all-new design with hundreds of improvements over version 6. The new menu bar modes include stacked labels and values, which helps when you’re monitoring multiple metrics. I particularly appreciate the Apple Silicon-specific features like frequency monitoring for individual cores and additional temperature sensors. On my M2 Air, I can see my efficiency cores running at different speeds than the performance cores, which is fascinating to watch during different workloads.
The app covers nine distinct monitoring categories: CPU and GPU (with detailed per-core usage, frequency, and temperature), memory (usage, pressure, compressed memory, swap), network (bandwidth, connection details, per-app usage), disk usage and activity (with S.M.A.R.T. status monitoring), time (with world clocks and calendar), battery (detailed power stats and health monitoring), sensors (temperatures and fan speeds throughout your Mac), and weather. There’s also a powerful Rules system that can notify you of events like high CPU usage, internet connectivity loss, or low disk space.
Performance impact is genuinely minimal. Despite monitoring all these metrics continuously, iStat Menus typically uses less than 1% CPU on my M2 Air and around 80-100MB of memory. Bjango’s claim of being “the most CPU-friendly system monitoring app” appears to be accurate - I’ve used competitors that consume significantly more resources while providing less information.
The customization options are extensive. Each menu bar item can be individually configured with different display modes (text, graphs, pie charts, combinations), colors, and update frequencies. You can reorder items by holding Command and dragging, and enable or disable entire modules as needed. I’ve configured mine to show minimal information in the menu bar (just CPU percentage and network speed) while keeping the detailed dropdowns one click away.
System requirements are macOS 11 Big Sur or newer. The app supports both Intel and Apple Silicon Macs, with specific optimizations for Apple Silicon processors. Pricing is $18 for a single license or $29 for a family pack (up to 5 family members). If you already own iStat Menus 6, upgrade pricing is available at a discount. The app is also available through Setapp subscription ($9.99/month for access to iStat Menus plus 250+ other apps).
One notable addition is the integrated weather feature, which requires a separate subscription and includes 6 months free with new purchases. While the weather integration is well-designed (showing detailed forecasts with temperature, wind, humidity, UV index, and more), I personally prefer dedicated weather apps and leave this disabled to reduce clutter.
The only minor friction I’ve encountered is the fan control feature, which allows manual fan speed adjustment with custom curves. While powerful, it’s something I’d recommend only for advanced users who understand thermal management - most people should let macOS handle this automatically.
For anyone who wants deep visibility into their Mac’s performance, iStat Menus is essential. Whether you’re troubleshooting performance issues, monitoring resource-hungry applications, tracking network usage, or simply curious about what’s happening under the hood, this app delivers unmatched detail with impressive efficiency. It’s premium software at a fair price, developed by Bjango, a respected independent developer known for quality Mac apps.
