Auto-progression
Your reps decide
next week's weight.
Log your sets. StackUp compares what you actually did to your target range and fills in the adjusted weight for next time — so the number is already there when you get to the rack.
- Free, no account needed
- No ads, ever
- Works offline
- 157 exercises, no limits
Bench Press · next session
37.542.5kg
You hit 14, 11 and 10 reps against a target of 8–10. Over the range, so the weight goes up — on its own, before you get to the rack.
What it is
A workout tracker that keeps up
StackUp is a free workout log for the gym floor. You write down what you lifted; it works out what you should lift next time. That is the whole product — there is no programme to follow, no coach to subscribe to, and nothing to read before you start.
Set up your split
Pick the days you train and the exercises on each. Or start a free workout and add things as you go.
Log your sets
Reps and weight, one tap each. The rest timer runs itself. Close the app mid-set and nothing is lost.
Next time is filled in
Finish, and every weight for the next session is already decided — up, down or unchanged.
Our promise
Your training, your rules
Most trackers are a filing cabinet: they hold your numbers and leave the thinking to you. StackUp is meant to be the other thing — something that pays attention while you train and has an opinion when you finish.
Yours to shape
Rep ranges, weight steps, rest length, set counts — every one is a setting, per exercise, not a default you live with. Change something mid-session and it counts for today only; your plan stays your plan.
A coach, not a logbook
It reads what you actually did and tells you what comes next, in plain arrows you can check yourself. No black box, and nothing behind a paywall.
Strength and cardio
Barbell, dumbbell, machine, cable and bodyweight, plus time-and-distance work on the bike or the treadmill — in the same log, on the same day.
Where it is going
Mobility work and more are on the way. StackUp is built by one person who trains, and nearly everything in it so far exists because somebody asked for it.
Inside the app
There is a lot more in here
Supersets, a rest timer that knows about rounds, cardio with a stopwatch, your numbers over time, and a library of 157 exercises to build from.
The rule
Three marks, and nothing hidden
Every suggestion comes from one comparison you can check yourself. No black box, no “AI”, nothing you have to pay to see.
It goes down as readily as up. A tracker that only ever adds weight is flattering you, not coaching you. Three bad weeks in a row and StackUp suggests a real deload instead of another small step down.
At the end
No spreadsheet. No maths at the rack.
You do not plan the next session. You finish this one, and the next one is already filled in. Every number is editable if you disagree — the app suggests, you decide.
What you get
Built for the gym floor
157 exercises, classified
Barbell, dumbbell, machine, cable, bodyweight and cardio — each with the muscles it actually works. Add your own in seconds.
Supersets and circuits
Group exercises and the rest timer waits between rounds, not between sets — which is the whole point of a superset.
Cardio with a stopwatch
Time and distance, with a clock that keeps running when you leave the app or your phone dies.
Sync, free
Sign in and your log follows you to another phone. Optional, and free — it is not the thing we would charge for.
Your data, exportable
One JSON file with everything in it, any time, from Settings. No lock-in and nothing held hostage.
German and English
Fully translated, not machine-translated — including all 157 exercise names.
Honestly
It is early, and that is the point
StackUp is young and built by one person who trains. There is no support queue: mail me and you get an answer, not a ticket number. Every feature in it so far came from someone asking.