How much battery does a screen-recording time tracker use?

The phrase “screen recording” sounds expensive: video encoding, spinning fans, an hour off your battery. A screen-recording time tracker is a different animal, because it does not record video.

The numbers

Dayflow captures about one frame every 10 seconds - 6 frames a minute, versus the 3,600 a real screen recording would take. In practice on Apple silicon that costs:

• ~100MB of RAM - about a tenth of one browser tab’s worth these days
• Under 1% CPU while recording
• Battery: minutes per day, not hours - the capture itself is a rounding error next to your display’s backlight

The honest caveat is AI analysis. Turning frames into a readable timeline takes a language model, and where that model runs decides the cost:

• Cloud or bring-your-own-key mode: the analysis happens elsewhere; your Mac only uploads periodic snapshots. Battery impact stays negligible.
• Local mode (Ollama / LM Studio): the model runs on your Mac in short bursts every few minutes. On an M-series Mac this is a brief, visible-but-small spike - the trade for nothing ever leaving your machine. On battery, expect a modest cost during those bursts, still nowhere near video-call territory.

Why this matters when picking a tracker

Automatic trackers run all day by definition, so their idle cost is the whole ballgame. When you compare options (the full comparison is here), the resource question splits the field more than the feature lists do: app-usage loggers like ActivityWatch are extremely light because they only read window titles; screenshot-based tools like Dayflow are nearly as light because stills are cheap; anything doing continuous video capture or constant cloud sync is the tier to be suspicious of.

A useful rule: if you can tell from your fan or your battery menu that a passive tracker is running, it is built wrong.

Check it yourself

Activity Monitor will settle it in thirty seconds: install Dayflow (free, open source, macOS 14+), let it run through a normal morning, then sort Activity Monitor by CPU and find it near the bottom of the list. The source code that keeps it that way is public.