# Fire Pump Calc vs OCMC

The clearest difference is update cadence: OCMC at monthly against Fire Pump Calc's every 8 months. Fire Pump Calc's advantage is device support (3 vs 1). On price, ads, in-app purchases and iOS requirement there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

Fire Pump Calc ships an update every 8 months, OCMC monthly. Both last shipped on October 1, 2026.

## The numbers

| Metric | Fire Pump Calc | OCMC |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.3 (4 ratings)](https://appshunter.io/ios/app/fire-pump-calc/id6739542307/reviews)** | — |
| Number of ratings | **4** | — |
| Positive reviews | 75.0% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 8 months | **Monthly** |
| Monetization | Free | — |
| Size | 6 MB | 70 MB |
| Requires iOS | **15.6** | 16.4 |
| Devices | **iPhone, iPad, iPod** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [Justin Medeiros](https://appshunter.io/developer/1782040504) | [Live Laps](https://appshunter.io/developer/1748038294) |

## What reviewers say

### Fire Pump Calc

[App page](https://appshunter.io/ios/app/fire-pump-calc/id6739542307)

This professional hydraulic calculator assists fire service professionals and students with complex calculations for pump operations. It accurately determines pump discharge pressure, friction loss, elevation changes, and appliance pressure loss, all designed for real-world fireground scenarios. The app works offline and requires no account for immediate use.

**Highlights:** Pump Discharge Pressure (PDP) calculation, Friction loss for any hose lay, Elevation gain and loss calculation, Appliance pressure loss, Nozzle pressure calculation, Offline functionality, No account required

**Features:** macOS Compatibility

**In-app purchases:** none


### OCMC

[App page](https://appshunter.io/ios/app/ocmc/id6746144967)

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

**In-app purchases:** none


## Frequently asked questions

### Is Fire Pump Calc free?

Fire Pump Calc is free to download, with no in-app purchases.

### Is OCMC free?

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

### Do Fire Pump Calc or OCMC have ads?

Neither Fire Pump Calc nor OCMC shows ads.

### Which is updated more often, Fire Pump Calc or OCMC?

Fire Pump Calc ships an update every 8 months, and OCMC monthly. Most recently, Fire Pump Calc was updated on October 1, 2026 and OCMC on October 1, 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.*