# Ruler vs 100cm Ruler

The clearest difference is ads: 100cm Ruler at none against Ruler's shown. 100cm Ruler also leads on rating (4.0 vs 3.7) and iOS requirement (12.0 vs 15.0). Ruler's advantage is review sentiment (63% vs 45%) and ratings volume (3 vs 1). On price, update cadence, in-app purchases and monetization model there is nothing between them.

Both are free to download. Ruler sells 1 one-off in-app purchase and 100cm Ruler sells 1 one-off in-app purchase. Whichever you choose, the download price is not the number that matters.

100cm Ruler holds the better App Store score, 4.0 against 3.7. Both are backed by a comparable volume of ratings — 3 and 1 respectively. Written reviews complicate that: 63% of Ruler's written reviews are positive against 45% of 100cm Ruler's, so the app with the better star average is not the one people write more warmly about.

Ruler ships an update every 5 months, 100cm Ruler every 3 months. The most recent releases landed on June 1, 2026 and June 11, 2026 respectively.

## The numbers

| Metric | Ruler | 100cm Ruler |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [3.7 (3 ratings)](https://appshunter.io/ios/app/ruler-scale-ruler/id919130707/reviews) | **[4.0 (1 ratings)](https://appshunter.io/ios/app/100cm-ruler/id982815744/reviews)** |
| Number of ratings | **3** | 1 |
| Positive reviews | **63.0% of reviews** | 45.1% of reviews |
| In-app purchases | Yes | Yes |
| Ads | Yes | **No** |
| Update frequency | Every 5 months | **Every 3 months** |
| Monetization | Free with in-app purchases | Free with in-app purchases |
| Size | 4 MB | 62 MB |
| Requires iOS | 15.0 | **12.0** |
| Devices | **iPhone, iPad, iPod** | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [mitsunori oishi](https://appshunter.io/developer/905649994) | [ZOOMO, Inc.](https://appshunter.io/developer/490112424) |

## What reviewers say

### Ruler

[App page](https://appshunter.io/ios/app/ruler-scale-ruler/id919130707)

This app displays various measurement scales for length, including meters and inches. It allows users to set magnification ratios and reduced scales for different applications. Users can calibrate the ruler and adjust PPI settings for accurate measurements.

**Highlights:** Display various measurement scales, Set magnification ratios, Set reduced scales, Measure in meters and inches, Free mode for custom scales, Calibration for accuracy, PPI setting

**Features:** macOS Compatibility, Family Sharing

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Hide Ads | $0.99 | one-time |


### 100cm Ruler

[App page](https://appshunter.io/ios/app/100cm-ruler/id982815744)

This app provides a digital ruler for measuring the length and diameter of small objects directly on your device. It features a millimeter scale and allows for easy sliding to measure.

**Highlights:** Digital ruler functionality, Millimeter scale, Diameter measurement, Screen sliding for measurement, Ad removal option

**Features:** macOS Compatibility

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Remove ADS | $1.99 | one-time |


## Frequently asked questions

### Is Ruler free?

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

### Is 100cm Ruler free?

100cm Ruler is free to download, with in-app purchases available.

### Which has better reviews, Ruler or 100cm Ruler?

100cm Ruler is rated higher. Ruler averages 3.7 out of 5 from 3 ratings, while 100cm Ruler averages 4.0 from 1 ratings.

### Do Ruler or 100cm Ruler have ads?

Ruler shows ads; 100cm Ruler does not.

### Which is updated more often, Ruler or 100cm Ruler?

Ruler ships an update every 5 months, and 100cm Ruler every 3 months. Most recently, Ruler was updated on June 1, 2026 and 100cm Ruler on June 11, 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.*