# 1RM Max Calculator vs Kalbox

The clearest difference is in-app purchases: Kalbox at none against 1RM Max Calculator's 3. Kalbox also leads on update cadence (every 2 weeks vs every 6 weeks). On price, ads, device support and iOS requirement there is nothing between them.

Both are free to download. 1RM Max Calculator sells 3 one-off in-app purchases. Kalbox asks for nothing beyond the download.

1RM Max Calculator ships an update every 6 weeks, Kalbox every 2 weeks. Both last shipped on October 21, 2026.

## The numbers

| Metric | 1RM Max Calculator | Kalbox |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.2 (22 ratings)](https://appshunter.io/ios/app/1rm-max-calculator/id1110502852/reviews)** | — |
| Number of ratings | **22** | — |
| Positive reviews | 70.4% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | Every 6 weeks | **Every 2 weeks** |
| Monetization | Free with in-app purchases | — |
| Size | 10 MB | 5 MB |
| Requires iOS | **16.6** | 17.0 |
| Devices | iPhone | **iPhone, iPad** |
| Age rating | 4+ | 4+ |
| Developer | [Kazumasa Shimomura](https://appshunter.io/developer/1110502851) | [KALBI LIMITED LIABILITY COMPANY](https://appshunter.io/developer/1551784600) |

## What reviewers say

### 1RM Max Calculator

[App page](https://appshunter.io/ios/app/1rm-max-calculator/id1110502852)

Instantly calculate your one-rep max (1RM) for bench press, squat, and deadlift using 7 scientific formulas. Track your progress with intuitive charts and calendar records. Ideal for athletes and lifters aiming for more scientific and effective training.

**Highlights:** 7 scientific 1RM calculation formulas, Supports bench press, squat, and deadlift, Progress tracking and data visualization, Calendar for daily record management, One-tap data saving, Offline functionality

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Calculator for deadlift | $2.99 | one-time |
| Calculator for squat | $2.99 | one-time |
| Ad Blocker | $2.99 | one-time |


### Kalbox

[App page](https://appshunter.io/ios/app/kalbox/id6767986664)

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases:** none


## Frequently asked questions

### Is 1RM Max Calculator free?

1RM Max Calculator is free to download, with in-app purchases available.

### Is Kalbox free?

Kalbox is free to download, with no in-app purchases.

### Do 1RM Max Calculator or Kalbox have ads?

Neither 1RM Max Calculator nor Kalbox shows ads.

### Which is updated more often, 1RM Max Calculator or Kalbox?

1RM Max Calculator ships an update every 6 weeks, and Kalbox every 2 weeks. Most recently, 1RM Max Calculator was updated on October 21, 2026 and Kalbox on October 21, 2026.

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*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*