Before you train
Plan your workout routines
Build reusable routines, group them into programs, or start an empty workout when plans change.
Upper/Lower Split Push/Pull/Legs Split
The workout tracker built for lifters
Plan. Train. Progress.
All in FLEX.
FLEX is a workout tracker for strength training. Build routines, log weights and reps, and track your progress—online or offline, on the web and iPhone.
No card required Works offline Private by design
Stay on pace 8 of 12 sets complete
67%
Automatic rest timer Running
1:30
1,273 exercisesUnique built-in movements
Offline-firstLog without a signal
Private by designYour data stays yours
Web + iPhoneTrain wherever you are
One connected training flow
From first set
to next milestone.
Plan the session, log the work, and use your history to make the next workout better.
After every session
Track your workout history
Search completed workouts and revisit exact sets, volume, duration, and exercise details.
15,042 lb volume 42 min duration
When you want options
Explore the exercise library
Search 1,273 unique built-in exercises with clear, consistent names, then keep custom movements beside them.
- Muscle filters
- Alphabet index
- Custom exercises
Your training history
The full picture,
set by set.
FLEX turns the work you already do into a clear record of where you’ve been and what comes next. Search sessions, revisit exact sets, and keep momentum visible.
- Fast workout search and filters
- Volume, duration, and exercise summaries
- Routines built from your real training
Workout history 01 / 04
Private by design
Your workout data
belongs to you.
Core tracking lives on your device. Create an account when you want secure backup and sync—not because the app demands it before your first set.
Local-firstYour workout keeps working offline.
Optional syncBack up across devices when you choose.
No ad machineYour training isn’t targeting data.
Before your first workout
Questions about FLEX
Get to know your workout tracker before you start logging.
What can I track with FLEX?
Log exercises, weights, reps, and sets during strength training. Build reusable workout routines, organize them into programs, and review completed sessions with volume, duration, and exercise summaries.
Is FLEX free to use?
You can start tracking workouts for free without a credit card. FLEX Pro is an optional upgrade for additional features. See the Free and Pro guide for plan details.
Can I log workouts offline?
Yes. FLEX stores core workout data on your device so you can log sets without a connection. Open the web app online first so it can load and cache its resources. Account sign-in, cloud sync, and AI features need an internet connection.
Do I need an account to use FLEX?
No. You can begin tracking as a guest with data stored locally. Create an account when you want backup and sync across devices. You can also export a FLEX backup from your profile.
Can I use FLEX in a web browser?
Yes. Open the FLEX web app on your phone, tablet, or computer. You can also install the web app on supported devices for easier access. Visit the FLEX documentation for platform and setup guides.
Your next session starts here
Everything you need.
One place to grow.
Bring your routines, your history, and your focus. FLEX grows with the way you train.
Start training free