Sadan

It tells you what to lift next.
And shows you why.

Sadan reads what you actually lifted and proposes the next session from it — a weight, a rep target, a lift that has stopped moving. The evidence behind every suggestion is right there, and you can overrule any of it.

Hebrew for “anvil.” Pronounced sah-DAHN.

Request a beta

The Android beta is running now, invite only, with everything unlocked. The iPhone version is coming soon to the App Store.

01 Strike

Log the set you just did

Weight, reps, how hard it felt. The screen is always about the set you just did — no forms to fill out between rounds, no fighting a timer to get a number in.

You are the hammer. The bar is the anvil. Sadan doesn't swing it for you. It waits until the blow has landed, then it looks at the steel.

Logging a set in Sadan: a Chest session with sets logged, a superset, and a rest timer running.
Logging a setWeight, reps, and how it felt — on the screen you're already looking at.
The plate calculator: 185 lb total shown as 45 and 25 per side on a 45 lb bar.
Loading the barWhat to hang on each side for the weight you're about to lift.

02 Recover

Most logging apps hold your numbers. This one reads them.

At the end of the session Sadan reads that record and makes a case: add weight, hold here, or back off. One sentence, with its reasoning in plain language.

It knows the difference between a hard session and a bad one. A grind at your target weight is information, not a failure. A poor night's sleep explains a weak day, and the plan shouldn't be cut because of it.

Sadan's read of a Legs session, explaining what the numbers showed and what it would do next.
The session readWhat happened, and the case for what to do next.

The numbers behind it

If you disagree, you can go see what it was reading.

Volume, progression per lift, and projected one-rep maxes estimated from the sets you logged. Every proposal is built on trends you can look at yourself.

Sadan trends for Flat DB Press: top set climbing to 80 lb × 10, projected 101 lb, and a note that every set on Sep 6 made 8 or better.
A lift over timeFlat DB press. Top set by session, a projected 1RM, and what Sadan can see across the sets.
Sadan volume trends in rows: weekly load in pounds for chest, back, shoulders, and arms over twelve weeks.
Volume by groupWeekly load, each row scaled to itself. What your training does not reach is listed too.
Chest weekly load totaling 128,725 lb, broken down by movement with Flat DB Press as the largest share.
What made the numberChest across eight movements, credited as primary — not a share of anything.
Sadan figures view: front and back muscle maps shaded from least work to the highest, with a bodyweight row below.
Where it landedLeast to your highest. The work, on the body.

03 Repeat

Squat · Deadlift · Bench · Press

Every rep
is a strike.

The bar is the anvil. You are the hammer. Strike. Recover. Repeat.

SADAN — every rep is a strike.

A proposed Chest day with Take it and Not this one buttons, and a note on what was left out.
Accept, edit, or rejectThe proposal waits on you. Nothing moves until you say so.

The proposal

It makes a case. It doesn't issue orders.

Every suggestion is a proposal. You accept it, edit the number, or reject it, and nothing in your plan changes until you do.

Take it. Not this one. Skip the read entirely and the app is still a clean training log. A second opinion at the end of a session — not a boss at the start of one.

The record

It stays on your phone

Your history stays on your phone. Nothing is sent unless you turn it on.

What you did: three personal records, 37 sets across 12 movements, and every set logged.
What you didRecords set, sets moved, and the note you left on the lift.
Session log: twenty-one sessions laid out week by week, each day marked with the group trained.
Your historyEvery session you've logged, week by week, on your device.

It shows its work.
Then it waits for you.

Details

  1. 01

    Logging that keeps up with you

    Weight, reps, and how the set felt. The screen is always about the set you just did — no forms to fill out between rounds, no fighting a timer to get a number in.

  2. 02

    A read on the session — and a case for the next one

    Ask for a read and Sadan summarizes what happened, then makes its case for what to do next, down to the working weights. It doesn't issue orders. Skip it entirely and the app is still a clean training log.

  3. 03

    The numbers behind the suggestion

    Every proposal is built on trends you can look at yourself — volume, progression per lift, and projected one-rep maxes estimated from the sets you logged. If you disagree with a suggestion, you can go see what it was reading.

  4. 04

    Pair with your own coachComing

    A trainer will be able to pair with you and see the same record and the same reasoning you do. It will work whether you're on the free tier or paying — your coach shouldn't be a feature you have to buy.

  5. 05

    It remembers what you told it

    Record an injury or a movement you're avoiding and it stays respected — no suggestion will quietly walk you back into it.

  6. 06

    Your training record stays on your device

    It stays on your phone. Nothing is sent unless you turn that path on:

    • —A session summary, when you ask for a read — sent to Anthropic. They don't train on it, and they delete it within thirty days.
    • —A copy to our server, if you turn on backup.Coming
    • —Whatever you choose to post, if you use the social side.Coming
    • —Your record, with a trainer you pair with.Coming
  7. 07

    Honest about limits

    Sadan is a training tool, not medical advice. It doesn't diagnose or treat anything, and it says so plainly rather than burying it. Anything to do with pain or injury belongs with a qualified professional.

Who it's for

A good fit

  • —You've been lifting long enough to have opinions about your own training.
  • —You follow a program and want something that tracks it without arguing with you.
  • —You want a second opinion at the end of a session, not a boss at the start of one.

Probably not

  • —If you want a workout handed to you every day with no say in it, there are better apps for that.
  • —If you're training around an injury, see a professional first. Sadan will tell you the same thing.

Questions

What's free, and what's Sadan Plus?
Free is the record: logging, your full history, and the charts of what you actually did. Plus is everything derived from it — the reads, the prescribed sessions, projected one-rep maxes, and progression over time. The principle is that we charge for what the app works out, never for what you lifted.
What does it cost right now?
Nothing. Plus is unlocked for everyone during the beta, and becomes a monthly subscription at 1.0. Your training record is yours either way, free tier or not.
Does it need an account?
No. Open it and start logging.
Does it work without a connection?
Logging does — that's all local, and it's most of what you do in the app. Asking for a read needs a connection, because that's the part that leaves the device. Backup, coach pairing, and social will each need one too, and each will be yours to turn on.
Is my training data used to train an AI?
No. When you ask for a read, a session summary goes to Anthropic. They don't train on it, and they delete it within thirty days. Your full record stays on your device. The privacy policy and consumer health data policy spell out the details, and govern if anything here reads differently.
Will it replace my coach?
No, and it shouldn't. A coach watches you move. Sadan reads numbers you typed in.
Is this medical advice?
No. Sadan is not a medical device and gives no medical advice. It doesn't diagnose, treat, or rehabilitate anything.

Support

[email protected]

Questions, bugs, or a suggestion the app got wrong — write in. A person reads it. More ways to reach us on the support page.

The next session

Request a beta invite

The Android beta is running now, invite only. Leave an email — it comes to us. A person reads it.