Stackweight

Get notified when we launch

Daily weigh-ins bounce. Stackweight turns sparse logs into weekly averages, pace, and projection — solo or with your trainer.

We'll only email you about the launch. See our Privacy.

What you get

Built for real logging, not perfect streaks

  1. Log in seconds

    Record weight fast. Sparse days are fine — you learn from what you logged.

  2. See the weekly truth

    Averages, change, and pace cut through daily noise so progress is readable.

  3. Train with context

    Trainers invite clients, follow the same trends, and run focused campaigns in one workspace.

  4. Solo or linked

    Use Stackweight on your own, or connect a trainer when it helps — without changing how you log.

Inside the app

Daily logs. Weekly truth.

Weigh-ins bounce day to day. Stackweight turns check-ins into stable weekly averages, change, and pace so you train the trend — not one noisy morning.

Campaign journal showing weekly weight averages, change, calorie averages, and pace toward target
  1. Pace and projectionSee whether you're on pace, your recent rate, and a projected end weight from the logged trend.
  2. Weekly averagesLog a few days each week. Avg and Change smooth the noise so progress is clear week over week.
  3. Day-by-day journalTap a day to record weight and calories (and fasting when you use it). Empty days are fine.
Pricing

Simple plans for solo use and trainers

Planned pricing at launch. Join the waitlist to get notified.

For individuals

Light

$5one-time

One 12-week campaign to try Stackweight — buy again after it ends.

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Most popularSave 33%

Individual

$12/mo
$8/mo

billed annually at $96

Full client app when you're not on a trainer's roster.

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For trainers

2 months free

Starter

$39/mo
$32.50/mo

billed annually at $390

Train up to 5 clients with invites and campaign tools.

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Most popular2 months free

Pro

$79/mo
$66/mo

billed annually at $790

Up to 25 clients for growing training practices.

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2 months free

Scale

$199/mo
$166/mo

billed annually at $1,990

Up to 100 clients for established training teams.

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2 months free

Unlimited

$349/mo
$291/mo

billed annually at $3,490

No client cap for larger training practices.

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FAQ

Questions, answered plainly.

Can I use Stackweight without a trainer?

Yes. Light gives you one 12-week campaign on your own; Individual unlocks the full client app when you are not linked to a trainer.

What is Light?

Light is a $5 one-time purchase for one 12-week campaign. After it ends, buy Light again or upgrade to Individual. The window runs from your campaign start date, not purchase day.

What happens when my Light campaign ends?

It becomes read-only. Upgrade to Individual to edit past campaigns and start new ones, or buy Light again for another 12 weeks. Prior Light campaigns stay read-only on your account.

What does trainer-covered access mean?

With an active trainer link, your trainer's subscription covers full client access through their current paid period.

Can trainers track for themselves?

Yes. Every trainer tier includes personal tracking in the client app at no extra seat cost — it does not count toward your client cap.

How many clients can a trainer take on?

Starter supports up to 5 clients, Pro up to 25, Scale up to 100, and Unlimited has no client cap.

What happens if a trainer cancels?

Linked clients keep full access through the trainer's paid-through date, then have 30 days of read-only access before needing their own plan to continue.

How do I manage or cancel a subscription?

Through the Polar customer portal — review billing and cancel there.