Built by a lifter, for lifters

Stop guessing
mid cut, bulk, or recomp

The scale lies day to day. Composition reads the trend behind your weigh-ins and Apple Health data, then tells you every week whether you’re holding muscle, dropping fat, or spinning your wheels.

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Coming to the App StoreFree for 14days at launch · no card
9:41
CompositionWk 5 · Jul 9
Current strategy
Cut
−0.7 kg/wk · protect muscle
5/8
On track
Clean cut. Fat’s coming off, muscle’s holding.
6/7 protein days · 4 sessions · −0.6 kg this wk
Fat mass · 8 weeksDetails ›
16.6 kg
−3.2 kg since May
APRMAYJUNJUL
Body fat
15.2% ↓0.4
Lean mass
64.8 held
  Syncs with Apple Health14-day trend smoothingLean vs. fat, colored by good / badCut · Bulk · Recomp · Maintain
The problem

You did everything right this week — and the scale went up.

Water, sodium, glycogen, a late meal — daily weight is mostly noise. Stare at it long enough and you’ll bail on a plan that was actually working, or ride one that isn’t. Serious training deserves a read you can trust.

How the verdict works

Three steps from raw data to a straight answer.

01
Sync your data

Pull weigh-ins and body-fat readings straight from Apple Health, or log them in a tap. No manual spreadsheets.

Raw daily readings
02
We find the trend

A 14-day smoothing filter strips out water and day-to-day chaos, leaving the real direction of your lean and fat mass.

Smoothed trend line
03
You get the verdict

Every week, one plain-language read against your goal — on track, off track, or stalled — with the drivers behind it.

On track
You’re recomping. The plan is working.
What you get

Made for people who actually train.

Lean vs. fat, split out

Not just weight. See muscle and fat move independently, each in its own color — green for gains, warm for fat.

+2.1 kg
Change since day one

Deltas colored by whether they’re good for your goal — so progress reads at a glance, no math.

CutBulkRecomp
A strategy, not just stats

Pick your phase and the verdict is read against it. A cut and a bulk are judged by different rules.

Apple Health, both ways

Reads your scale and body-fat data automatically, writes composition back. Your smart scale already feeds it.

Raw or smoothed

Trust the trend by default, flip to raw dots when you want to see every data point. Your call.

62.7→64.8
The long arc

6 weeks to a year of history — start, now, change, and per-week rate, so you see the whole block.

Inside the app

Read the week. Dig into the arc.

9:41
CompositionWk 12
Current strategy
Recomp
Hold weight · shift composition
12/16
On track
You’re recomping. The plan is working.
6/7 protein days · 4 sessions
Lean mass · 12 weeks
64.8 kg
+2.1 since Apr
APRMAYJUNJUL
Body fat
15.2% ↓0.4
Fat mass
16.6 kg
Home · the weekly read
9:41
Trend
LeanFatWeightBF%
Lean mass
64.8 kg
+2.1 kg
Since Apr 14
6W3M6M1YAll
Start
62.7
Now
64.8
Per wk
+0.18
Trend · the long arc
Works with your setup

Your smart scale already does the logging.

Composition reads weight and body-fat data from Apple Health the moment you step off the scale, and writes your computed lean and fat mass back. No new hardware, no double entry.

 Apple HealthSmart scales
Apple Health
Connected
Body Mass↓ read
Body Fat %↓ read
Lean Body Mass↓ read
Early access

Track the signal.
Trust the plan.

We’re building Composition for iPhone now. Drop your email and you’ll be first in line when it hits the App Store — free for your first 14 days.

By joining, you agree to receive launch emails from Composition. See our Privacy Policy. Unsubscribe anytime.

Coming to the App StoreNo spam · one launch email