You track everything. Except your focus.

Today, according to your devicessample numbers

Steps8,412
Sleep7h 12m
Heart rate58bpm
HRV62ms
Calories540kcal
Blood oxygen98%

Focus leftno data

9:00 AMOne Tuesday, in 13 seconds

No sensor for this one. It's the thing you work with all day.

Your brain has a battery too. FocusOS is a tiny Mac widget that estimates how much is left.

The missing one

It drains all day. You only notice when it's empty.

No sensor can read focus. But your Mac sees what spends it: every switch, every feed, every break. That's enough for an honest estimate.

Meet the buddy

Not on your wrist. On your screen.

So we put that estimate where you can't miss it. The buddy is a thin line on the edge of your Mac's screen, and it grows a face when it has something to say.

that's the buddy. click it →

One Tuesday, lived twice

Same person. Same job. One of them can see the battery.

Your step count won't tell you where a workday went. The missing number will. Here's one Tuesday, run twice: once blind, once with the battery in view.

9:00 AMsample day

On autopilot

100%Working on the report

Battery in view

100%Working on the report

10:32 AM
The "quick" scroll.
On autopilot: you open a feed for a second. Fifteen minutes later it's still open. In our model, nothing drains faster.
Battery in view: you watch it drop while the feed is open. The buddy leans out. In this sample, you're back in three minutes.
12:45 PM
Lunch.
On autopilot: lunch at your desk, feed open. A break that drains.
Battery in view: you walk away for half an hour and come back charged.
2:38 PM
The slump.
On autopilot: you push through with more tabs and a video.
Battery in view: the buddy suggests a break. Ten minutes of looking at nothing, then back in.
4:30 PM
The thing that mattered.
The hard part of the report lands here. In this sample, autopilot has – left. Battery in view has –.
Same day, same job. The only difference: one of them saw the cost as it happened.

Open the buddy

Morning: three tasks. Evening: where your focus went.

Click the buddy and it opens.

66%Focused 22 min

Now

Three things, not thirty.

A long to-do list is one more place to get lost. The buddy holds three tasks and keeps the one you're on at the edge of your screen. Drift, and there's something specific to come back to. Try it: tick one off.

Tuesday on autopilotsample day

Time on work–

Switches–

Feeds + video–

Longest stretch–

Where the day went.

Most people guess where their day went. This shows it: what drained you, what refilled you, and the one change that would have saved the most.

What it tracks

Three signals. Nothing leaves your Mac.

No sensor needed. It uses three things your Mac already knows.

SIGNAL 1

Which app is in front

Every time the front app changes, that's a switch. Each one costs the same small amount, work or not. It's the hopping that adds up.

front app: Slack → switch, −0.07%

SIGNAL 2

Which site the tab is on

Only the address, never the page. That's how it tells a feed from a doc, and spots when you return to something you left a while ago. Chrome only for now.

tab: instagram.com → feed, −0.45% a minute

SIGNAL 3

Whether you're at the keyboard

No keyboard or mouse for 3 minutes means you stepped away, and the battery charges. It can tell that you're active, never what you type.

no input 3 min → away, charging

How sure we are

It's a forecast, not a blood test.

The battery adds up effects that attention studies have found. Below: what's solid, what's our guess, and what we don't claim. Every day on this page is a sample run of the model, not real data.

Solid

Hard thinking tires you over hours. Across 2 million school tests, scores dropped for every hour later in the day, and a 20 to 30 minute break won it back. Sievertsen 2016
Even short interruptions cost. A 2.8-second interruption doubled errors on a sequence task. Altmann 2014
We switch constantly. People stayed on one screen for about 47 seconds on average. Mark 2023
Interrupted work takes a while to pick up. About 25 minutes on average in one office study. Mark 2005

Our best estimate

The exact exchange rates. Nobody has measured how many switches equal a minute of scrolling. The rates are our own calibration, fitted to these studies. Expect them to change as the beta teaches us.
Feeds drain fast. A phone break left people as drained as no break. Kang 2019 A short-video feed hurt remembering what you meant to do. Chiossi 2023 The per-minute rate is ours.
Quiet rest refills fastest. Ten minutes of doing nothing helped memory in a small study. Dewar 2012 Short breaks cut fatigue. Albulescu 2022

What we don't claim

"Willpower is a tank that runs out." The famous decision-fatigue experiments didn't hold up in two large repeats with over 5,000 people. Hagger 2016 Vohs 2021
So we don't count decisions. We count switches, because the cost of an interruption has been measured. How much each one costs is our estimate.
That seeing the battery changes what you do. We think it does. The beta is how we find out.
A low battery never means you can't. It means a short break will pay off more than usual right now.

The 30-second nothing test

Can you do nothing for 30 seconds?

No mouse. No keys. No scrolling. No other tab. Just look at the screen. Harder than it sounds.

0.0s

Any move ends it.

The Mac app

Put the battery on your Mac.

Shows your battery on the edge of the screen.
Holds three tasks. The current one stays in view.
Nudges you when you drift into tabs or a feed.
Suggests a 10-minute break when you're low.
Every evening: where your focus went, and what to change.
Stays on your Mac. Never reads your screen or what you type.

Free private betamacOS 13 or laterOne permission: which Chrome tab is in frontMade by Lost Astronaut

FocusOSDocs

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