Comparison

531 Strength vs JuggernautAI

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

531 Strength

This app simplifies tracking your progress on the 5/3/1 strength training program. It calculates and displays weights, reps, and sets based on your one-rep max, allowing you to easily plan and execute your workouts. Rounding options help match available gym plates.

Highlights
  • Calculate 5/3/1 weights
  • Track 1RM for exercises
  • View cycle step weights
  • Round weights to available plates
  • Full overview of weights, reps, sets
Features
Read full description

Makes it quick and easy to get a full overview of all weights, reps and sets based off your 1RM when you’re following the 5/3/1 program. - Save your current 1 RM for each of the four exercises - View calculated weights for each step in the cycle - Round the weight to match the plates you have available This app is made for people who are familiar with the structure of the 5/3/1 program and who needs simple access to the calculated weights for each exercise.

About

JuggernautAI

This app uses AI to create personalized strength training programs for powerlifting and powerbuilding. It adapts to your feedback and goals, optimizing volume, frequency, and exercise selection for maximum strength gains and recovery.

Highlights
  • AI-generated personalized workout plans
  • Powerlifting and Powerbuilding goal focus
  • Adaptive training based on real-time feedback
  • Optimized training frequency and volume
  • Exercise selection for weak points
  • Periodization strategy for fatigue management
Features
Read full description

Juggernaut Training Systems’ revolutionary A.I. strength training system has arrived on iOS. Subscribe to JuggernautAI to access all our coaching and get stronger than you can imagine with The Smartest Program for You. Designed by legendary coach Chad Wesley Smith with revolutionary technology by Tim Arnold, JuggernautAI is like having the best strength coach in the world with you during every workout in the gym. HOW IT WORKS JuggernautAI helps you reach your strength potential using our cutting edge technology - the JuggernautAI Powerlifting and Powerbuilding system - in an efficient and easy to use way; Decide on your goal of Powerlifting, to focus on building your Squat, Bench, and Deadlift, or Powerbuilding, to balance your focus between bodybuilding and strength training. Tell us about yourself, your level of experience, and your strength goals JuggernautAI will then design a unique individualized program tailored just for you with the use of expert technology As you progress, the system will continue to adapt your training plan based on your real-time individualized feedback, ensuring you continue to grow and achieve your strength goals. WHY IT WORKS Your JuggernautAI strength program is specifically tailored to your needs and includes; ◆◆ Individualized Volume Landmarks. Do enough training to advance but not so much that you can’t recover. ◆◆ Optimized Training Frequency. Decide how many days a week you want to train, and JuggernautAI will optimize when and how often you should Squat, Bench, and Deadlift. ◆◆ Personalized Periodization Strategy. JuggernautAI finds the best way to progress to ensure you maximize your training while also managing fatigue through a strategic phasic periodization plan. ◆◆ Exercise Selection for your Weak Points. JuggernautAI looks at your weak points and your strength in individual lifts to decide which exercises will be most effective in helping you improve. As a Powerbuilding user, you can also choose which body part to focus on to ensure your physique improves the way you want it to. ◆ Real-Time Feedback Your unique individualized program continues to adapt to your feedback with our Readiness Rating System, making adjustments to your program pre-session, intra-session, session to session, week to week, block to block, and program to program Subscribe to JuggernautAI and get the smartest program for you. ———- ABOUT JUGGERNAUT TRAINING SYSTEMS Juggernaut Training Systems is The Leader in Strength, having helped thousands of athletes from beginners to World Champions maximize their results and reach their goals. We deliver principle-based coaching through cutting-edge technology to help you get the best results of your life. Privacy Policy: https://www.jtsstrength.com/app-privacy-policy/ Terms of Use: https://www.jtsstrength.com/app-terms-of-use/

Screenshots

531 Strength4 screens
JuggernautAI4 screens

Verdict

The call

The clearest difference is monetization model: 531 Strength at free with in-app purchases against JuggernautAI's subscription. 531 Strength also leads on review sentiment (94% vs 73%). JuggernautAI's advantage is ads (none vs shown) and update cadence (every 4 days vs every 2 months). On price, rating, ratings volume and in-app purchases there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. 531 Strength sells 4 one-off in-app purchases and JuggernautAI sells 1 in-app purchase, starting at $34.99 per month. Whichever you choose, the download price is not the number that matters.

ReceptionRating · Positive reviews · Number of ratings

On the App Store both sit at effectively the same score — 4.9 for 531 Strength against 4.8 for JuggernautAI. Both are backed by a comparable volume of ratings — 12K and 5.7K respectively. Written reviews are what separate them: 94% of 531 Strength's written reviews are positive against 73% of JuggernautAI's.

UpkeepUpdate frequency

531 Strength ships an update every 2 months, JuggernautAI every 4 days. Both last shipped on September 23, 2026.

Scorecard5 real differences · 5 level
531 Strength versus JuggernautAI: the parameters behind the verdict, then further details
Parameter531 StrengthJuggernautAI
PriceFreeFree
Rating4.9 (12K ratings) — better4.8 (5.7K ratings)
Positive reviews93.8% of reviews — better72.7% of reviews
Number of ratings12K — better5.7K
Update frequencyEvery 2 monthsEvery 4 days — better
AdsYesNo — better
In-app purchasesYesYes
MonetizationFree with in-app purchases — betterSubscription
DevicesiPhone, iPadiPhone, iPad, iPod — better
Requires iOS17.615.6 — better
Further details — not scored
Size28 MB108 MB
Age rating4+17+
DeveloperHenrik JachobsenJuggernaut Apps

Customer experience

531 Strength

All ratings11,581 ratings
Positive98.0%
Neutral1.2%
Negative0.8%
Written reviews272 reviews
Positive93.8%
Neutral2.9%
Negative3.3%

JuggernautAI

All ratings5,654 ratings
Positive97.0%
Neutral1.2%
Negative1.7%
Written reviews216 reviews
Positive72.7%
Neutral4.2%
Negative23.1%

User reviews

531 Strength

From 12K App Store ratings

What we love

  • 🚀 Simple and efficient
  • 👍 Intuitive interface
  • 💪 Helps with strength gains
  • 🔧 Customizable features
  • ⏱️ Convenient timer

Room to improve

  • 🔢 Inaccurate percentage calculations
  • 🗓️ Lack of ability to plan future workouts
  • 📋 Limited exercise tracking
  • 💰 Paid features not worth the cost

JuggernautAI

From 5.7K App Store ratings

What we love

  • 🚀 Excellent programming and customization
  • 👍 Detailed and user-friendly app
  • 🔍 Adjusts based on user feedback
  • 📈 Helps users achieve their goals
  • 💪 Effective for building strength and muscle

Room to improve

  • 💰 Expensive monthly subscription
  • 🔒 Paywall restricts access to full app
  • 🕰️ Excessive time required for workouts
  • 🐛 Occasional bugs and glitches

Bugs and requests

531 Strength

Reported bugs

2 issues
  • Rest timer stops when app is backgrounded
  • Plate calculator not flexible enough

Requested features

4 requests
  • Ability to adjust training max separately from 1RM
  • Option to track rep PRs and estimated 1RM
  • Accessory exercise tracking and planning
  • Sync progress across devices

JuggernautAI

Reported bugs

3 issues
  • Clearing of workout history after each block
  • Issues with the auto-timer feature
  • Problems with selecting dates and times during setup

Requested features

4 requests
  • Integration with Apple Health or other fitness apps
  • More flexibility in scheduling and workout days
  • Improved exercise library and replacement options
  • Better tracking and history of past workouts

In-app purchases

4 purchases

531 Strength

One-time4
  • Additional exercises$1.99
  • Adjustable set$1.99
  • Plate calculator$1.99
Show 1 more
  • Progress log$6.99
1 purchases

JuggernautAI

Subscriptions1
  • JuggernautAI Monthly2 variants$34.991 Month

Questions

Is 531 Strength free?
531 Strength is free to download, with in-app purchases available.
Is JuggernautAI free?
JuggernautAI is free to download, with in-app purchases available.
Which has better reviews, 531 Strength or JuggernautAI?
531 Strength is rated higher. 531 Strength averages 4.9 out of 5 from 12K ratings, while JuggernautAI averages 4.8 from 5.7K ratings.
Do 531 Strength or JuggernautAI have ads?
531 Strength shows ads; JuggernautAI does not.
Which is updated more often, 531 Strength or JuggernautAI?
531 Strength ships an update every 2 months, and JuggernautAI every 4 days. Most recently, 531 Strength was updated on September 23, 2026 and JuggernautAI on September 23, 2026.

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