# Millimeter Pro vs Duck Calculator

The clearest difference is review sentiment: Duck Calculator at 100% against Millimeter Pro's 58%. Duck Calculator also leads on price ($0.99 vs $3.99). On update cadence, ads, in-app purchases and device support there is nothing between them.

Millimeter Pro costs $3.99 and Duck Calculator $0.99 up front. Neither carries in-app purchases, so what you see is what you pay.

Millimeter Pro ships an update every 4 months, Duck Calculator every 7 months. The most recent releases landed on November 6, 2026 and November 4, 2026 respectively.

## The numbers

| Metric | Millimeter Pro | Duck Calculator |
| --- | --- | --- |
| Price | $3.99 | **$0.99** |
| Rating | **[4.4 (109 ratings)](https://appshunter.io/ios/app/millimeter-pro-screen-ruler/id631810777/reviews)** | — |
| Number of ratings | **109** | — |
| Positive reviews | 57.9% of reviews | **100.0% of reviews** |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Every 4 months** | Every 7 months |
| Monetization | **Free** | Paid |
| Size | 24 MB | 1 MB |
| Requires iOS | **15.0** | 16.0 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [VisTech.Projects LLC](https://appshunter.io/developer/620969851) | [德铭 何](https://appshunter.io/developer/1690983330) |

## What reviewers say

### Millimeter Pro

[App page](https://appshunter.io/ios/app/millimeter-pro-screen-ruler/id631810777)

This app transforms your device into a versatile measuring tool. It allows for precise measurements of length, area, diameter, and angles using the touchscreen. Easily split objects into equal parts and switch between millimeters and inches for your convenience.

**Highlights:** Touchscreen ruler and tape measure, Measure length, area, diameter, and angles, Split objects into equal parts, Supports millimeters and inches, Estimate radius, Thread pitch gauge

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

**In-app purchases:** none


### Duck Calculator

[App page](https://appshunter.io/ios/app/duck-calculator/id6739608733)

This app appears as a standard calculator but has a hidden "magic" mode. It can display preset text or images when a specific number is calculated, offering creative surprises for pranks or confessions.

**Highlights:** Accurate standard calculations, Magic mode for custom results, Display preset text or pictures, Customizable magic effects, Secret and low-key design

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

**In-app purchases:** none


## Frequently asked questions

### Is Millimeter Pro free?

Millimeter Pro costs $3.99, with no in-app purchases.

### Is Duck Calculator free?

Duck Calculator costs $0.99, with no in-app purchases.

### Do Millimeter Pro or Duck Calculator have ads?

Neither Millimeter Pro nor Duck Calculator shows ads.

### Which is updated more often, Millimeter Pro or Duck Calculator?

Millimeter Pro ships an update every 4 months, and Duck Calculator every 7 months. Most recently, Millimeter Pro was updated on November 6, 2026 and Duck Calculator on November 4, 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.*