Know your fitness.
Train to
improve it.
VO2 Maximizer turns your VO2 max into a starting point. Run a guided field test, follow HIIT or Zone 2 workouts, and track your progress.
Free download · In-app purchasesField tests estimate VO2 max.
Your next step,
made clear.
Start where you are today.
Find your
starting point.
Choose a field test that fits your space and equipment. Get an estimate and compare it with age and sex norms.
Find my test ↗I WANT TO TRAINGive each workout
a purpose.
Follow Norwegian 4×4, build your own intervals, or choose a guided Zone 2 session.
Explore the workouts ↗I WANT TO SEE MY PROGRESSLook beyond
a single number.
Review your test history and training. Repeat a test to see how your performance has changed.
See the progress tools ↗The tools to turn
a baseline into a plan.
Guided tests, purposeful workouts and a clear record of your progress.
Five ways to find
your starting point.
Beep, Yo-Yo, Cooper, Balke and 2.4 km / 1.5 miles. Follow the cues and estimate your VO2 max from your performance.
Which test should I take? ↗Follow a protocol.
Make it your session.
Norwegian 4×4, Tabata or intervals you build yourself.
rhythm.
Build your base.
Stay in your zone.
Follow a steady Zone 2 session. Your Apple Watch cues you when your heart rate drifts out of range.
Meet your easier days ↗
Leave your phone
in the bag.
Tests, workouts, audio and haptics. All on your wrist.
Made for Apple Watch ↗See what changes.
Keep the context.
Review your heart-rate zones, effort and training history alongside your test results.
Look closer ↗
Find your place.
Compare eligible results on a global leaderboard, with checks on submitted scores.
Field tests estimate VO2 max; they do not directly measure oxygen consumption as a laboratory test does.
A plan for your weeks.
Context for your days.
Your next workout, your readiness and the bigger picture in one app.
A plan for your next 12 weeks.
Structured sessions based on your starting fitness, with your next workout ready to follow.
Daily readiness.
HRV, sleep and recent training load come together to help put your day in perspective.
Fitness age.
See your cardiovascular fitness in a different light, alongside your VO2 max trend.
Race predictions.
Explore estimated race times from 5K to marathon, based on your current fitness.
Norms by age and sex.
Put a test result in context and follow how your own performance changes. See the tables ↗
Apple Health, connected.
Bring supported health data and workouts into your training history.
Understand
your estimate.
Each test guide explains the setup, published equation and limits behind your result. Field tests estimate VO2 max from your performance; laboratory tests directly measure oxygen consumption.
Explore the test methods ↗Built by Kevin Floc'h.
A clear explanation of what the app does, how its tests work, and where to get help.
Meet VO2 Maximizer ↗Ask a question ↗From people putting in the work.
Two reviews from the App Store.
“I've been using this app for 2 years, including as a beta tester, and the progress has been huge.”
“Most complete app regarding Vo2 max training. Very nice Apple Watch app too.”
Understand your number.
Choose your next step.
Practical guides to testing, VO2 max scores and training.
What Your VO2 Max Score Actually Means
Got a VO2 max number from a lab, field test, or watch? Here is what your score translates to on the FRIEND chart, and what to actually do with it.
Read the guide ↗
How to Run a Beep Test (Step-by-Step Guide)
The 20-meter shuttle test setup, warm-up, pacing strategy, and stop criteria. Everything you need to run a clean beep test from your first attempt.
Read the guide ↗
How to Improve Your VO2 Max: 12-Week Plan
The 12-week training plan that lifted my VO2 max by 6 mL/kg/min: zone-2 base, threshold blocks, HIIT, and the supporting work that actually moves the number.
Read the guide ↗Before your first session.
What does this VO2 max app do?
VO2 Maximizer brings guided field tests, HIIT, Zone 2 workouts and progress tracking to iPhone and Apple Watch. Field tests estimate VO2 max from your performance; they do not replace a direct laboratory measurement.
Do I need an Apple Watch?
The app is available on iPhone and Apple Watch. Watch adds wrist-based heart rate and cues. Check the requirements for your chosen test or workout in the app.
Does a field test measure my VO2 max directly?
Field tests estimate VO2 max from performance. They do not replace a direct laboratory assessment of oxygen consumption.
Can I create my own workouts?
Yes. Create your own interval blocks or use a built-in preset.
Where can I see current prices?
The app is free to download with in-app purchases. Apple shows current regional pricing and eligible offers before you confirm a purchase.
Find your starting point.
Build from there.
Five field tests. Guided workouts. Your progress in one app.
Get VO2 Maximizer ↗