verdict
Use iStat Menus if you want the most polished menu-bar monitor on the Mac and are happy to pay for it. Version 7.5 costs $11.99, has a 14-day trial, and does things plottypus 1.0.0 does not: notifications on a wide range of events, fan control with curves tied to temperature or battery state, weather, and a combined menu-bar mode. Use plottypus if you work in a terminal or over ssh, want a full process table with per-process watts and signals, want the numbers as JSON, or want CPU watts on macOS 27 without sudo. plottypus is free.
At a glance#
Checked 2026-09-24 against Bjango’s product page and store. We did not run iStat Menus on our test machine for this page, so its rows list what Bjango documents, not what we measured.
| plottypus 1.0.0 | iStat Menus 7.5 | |
|---|---|---|
| CPU watts on macOS 27 | Yes. Live from SMC power rails on the M5 Pro; other chips get the last IOReport batch, marked ≈ with its age |
Not checked on macOS 27 |
| GPU MHz / °C | Yes / yes | GPU usage, memory, temperature and frequency “on supported Macs” |
| Per-cluster clocks | Super, Performance and Efficiency clusters with MHz | CPU frequency; efficiency and performance cores styled separately |
| Per-process energy / GPU | Watts per process; GPU share in the details card | Apps using the most CPU and memory |
| Needs sudo | No | Not checked |
| Self-cost | ~1.5% of one core at 500 ms, ~1.0% at 1 s (our measurement) | Not measured |
| Works over ssh / in tmux | Yes | No, it is a menu-bar app |
| Process actions | TERM, KILL, INT, STOP/CONT, any signal, renice, background QoS | Not documented on the product page |
| Alerts | Not in 1.0.0 (planned for Pro, not on sale) | Notifications on CPU, GPU, memory, disks, network, sensors, battery, power and weather |
| Fan control | No, read-only | Yes, including temperature- and battery-based curves |
| JSON output | --json, --json-stream |
Not documented on the product page |
| Platforms | macOS on Apple Silicon only | macOS 11 or later |
| Price / licence | Free download, proprietary EULA; a paid Pro tier is planned, not on sale | $11.99 one-time ($14.99 family pack, $9.99 upgrade from 6); also in Setapp |
Sources: iStat Menus product page (version, requirements, trial, features), prices from Bjango’s Paddle checkout for the US on 2026-09-24.
Where iStat Menus is ahead#
It is a mature product for people who want their Mac’s vitals in the menu bar. Alerts and fan control are two things plottypus does not have: plottypus 1.0.0 only reads the SMC and has no fan control, and its alerts are planned for a Pro tier that is not on sale yet. If you want a notification when the CPU stays pegged, or fans that ramp on your own curve, buy iStat Menus.
Where plottypus is different#
plottypus is a terminal program. That means:
- it runs over ssh, in tmux, and in a terminal split next to the build it is watching;
- it prints what it sees as JSON (
plottypus --json, or one line per interval with--json-stream); - it answers “why is the fan on” in one line:
plottypus --diagnoseprintsAll normal,Busy: rustc using 9.1 coresorHot: fans at 80%with its evidence.
It also has the whole process table, not a top list: filter, sort by any column, tree, per-process watts, GPU share, footprint memory, disk I/O and wakeups, and signals including STOP/CONT, renice and background QoS. A kill is refused if the pid was reused since you selected it.
CPU watts on macOS 27#
On macOS 27, IOReport’s CPU energy counter publishes in batches, 2 to 108 seconds apart in our captures. Tools that divide its change by the sampling interval show 0 W between batches; we measured macmon at 0.0 W in 20 of 20 one-second samples on an M5 Pro. We have not checked how iStat Menus handles this. The long version, with the raw captures: why macOS 27 shows 0.00 W CPU power.
plottypus reads the SMC’s CPU power rails on the M5 Pro, and elsewhere divides the IOReport change by the driver’s own timestamps, holds it between batches with its age, and shows — once it is more than 10 s old.
Using both#
They don’t conflict. iStat Menus in the menu bar, plottypus in a terminal when you need to see which process is doing it. If you already pay for iStat Menus, plottypus costs nothing to add.