# Stoichiometry vs Sift Science

The clearest difference is price: Sift Science at Free against Stoichiometry's $2.99. Sift Science also leads on update cadence (every 2 days vs every 2 months). Stoichiometry's advantage is in-app purchases (none vs 2). On ads, device support and iOS requirement there is nothing between them.

Sift Science is free to download; Stoichiometry costs $2.99 up front. Sift Science sells 2 in-app purchases, starting at $4.99 per month. Stoichiometry asks for nothing beyond the download.

Stoichiometry ships an update every 2 months, Sift Science every 2 days. The most recent releases landed on November 13, 2026 and October 31, 2026 respectively.

## The numbers

| Metric | Stoichiometry | Sift Science |
| --- | --- | --- |
| Price | $2.99 | **Free** |
| Positive reviews | 50.0% of reviews | — |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 2 months | **Every 2 days** |
| Monetization | Paid | — |
| Size | 1 MB | 83 MB |
| Requires iOS | **17.1** | 18.6 |
| Devices | **iPhone, iPad** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [Roman Volinsky](https://appshunter.io/developer/977951850) | [Shobel LLC](https://appshunter.io/developer/1298270459) |

## What reviewers say

### Stoichiometry

[App page](https://appshunter.io/ios/app/stoichiometry/id1330949637)

This tool helps balance chemical reactions and calculate molar masses, moles, and actual masses of reactants and products. It supports various formula formats and can identify limiting reagents. Data can be sent to another app for gas phase calculations.

**Highlights:** Balance chemical reactions, Calculate molar masses, Determine moles and actual masses, Identify limiting reagents, Supports various formula formats, Integrates with Gas Phase Stoichiometry app

**Features:** Vision Pro support

**In-app purchases:** none


### Sift Science

[App page](https://appshunter.io/ios/app/sift-science/id6767901370)

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

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Sift Premium Monthly | $4.99 | per month |
| Sift Premium | $39.99 | per year |


## Frequently asked questions

### Is Stoichiometry free?

Stoichiometry costs $2.99, with no in-app purchases.

### Is Sift Science free?

Sift Science is free to download, with in-app purchases available.

### Do Stoichiometry or Sift Science have ads?

Neither Stoichiometry nor Sift Science shows ads.

### Which is updated more often, Stoichiometry or Sift Science?

Stoichiometry ships an update every 2 months, and Sift Science every 2 days. Most recently, Stoichiometry was updated on November 13, 2026 and Sift Science on October 31, 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.*