# VO2 Max Calculator vs Open

The clearest difference is price: Open at Free against VO2 Max Calculator's $1.99. Open also leads on update cadence (every 2 weeks vs every 7 months). On ads, in-app purchases, device support and iOS requirement there is nothing between them.

Open is free to download; VO2 Max Calculator costs $1.99 up front. Neither carries in-app purchases, so what you see is what you pay.

VO2 Max Calculator ships an update every 7 months, Open every 2 weeks. The most recent releases landed on November 3, 2026 and October 27, 2026 respectively.

## The numbers

| Metric | VO2 Max Calculator | Open |
| --- | --- | --- |
| Price | $1.99 | **Free** |
| Rating | **[2.4 (14 ratings)](https://appshunter.io/ios/app/vo2-max-calculator/id1586812282/reviews)** | — |
| Number of ratings | **14** | — |
| Positive reviews | 38.5% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 7 months | **Every 2 weeks** |
| Monetization | Paid | — |
| Size | 1 MB | 30 MB |
| Requires iOS | 15.6 | **15.0** |
| Devices | iPhone, iPod, Apple Watch | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Theo Scott](https://appshunter.io/developer/691156625) | [Elaros](https://appshunter.io/developer/1544802505) |

## What reviewers say

### VO2 Max Calculator

[App page](https://appshunter.io/ios/app/vo2-max-calculator/id1586812282)

This app calculates your VO2 Max in just 3 minutes using a simple heart rate method. It's based on scientific research and provides general health information, not medical advice.

**Highlights:** Passive VO2 Max reading, 3-minute calculation, Based on scientific research, General health information, Video tutorial available

**Features:** Apple Watch app

**In-app purchases:** none


### Open

[App page](https://appshunter.io/ios/app/open-oh/id6502186049)

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

**In-app purchases:** none


## Frequently asked questions

### Is VO2 Max Calculator free?

VO2 Max Calculator costs $1.99, with no in-app purchases.

### Is Open free?

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

### Do VO2 Max Calculator or Open have ads?

Neither VO2 Max Calculator nor Open shows ads.

### Which is updated more often, VO2 Max Calculator or Open?

VO2 Max Calculator ships an update every 7 months, and Open every 2 weeks. Most recently, VO2 Max Calculator was updated on November 3, 2026 and Open on October 27, 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.*