Fast, accurate density altitude app: altimeter setting, relative air density (RAD) and more using your device's onboard sensors and detailed physics calculations.

Instant and location accurate Density Altitude calculator/instrument app for iPhone and iPad that also finds relative air density (RAD), altimeter setting, relative humidity, specific humidity (grains/lb) and more. Super useful for pilots, especially in the backcountry. Many other uses for engine tuning, racing, sports, etc.

* Seamlessly integrates weather data, GPS and your phone's onboard barometer to quickly and accurately calculate your density altitude, altimeter setting, relative air density, and more.

* Takes humidity into account in all calculations, making it more accurate than the typical dry bulb approximation formula used by AWOS/ASOS, etc.

* Works anywhere. Great without cellular connection as well, which makes it all the more useful in the backcountry and far away from ASOS/AWOS stations.

Data Sensed and Calculated (all calculated with humidity):

* Density Altitude
* GPS Altitude
* Temperature
* Altimeter Setting
* Absolute Pressure
* Dew Point
* Relative Humidity
* Specific Humidity (grains/pound)
* Air Density
* Relative Air Density (RAD)
* Dyno Correction

The quickest way to get your Density Altitude! On the iPhone 6/6+ and newer iPads, it will use the built-in barometer and GPS. If you're in cell range, you don't need to supply any data. If you're out of cell range, all you need to supply is the outside air temperature. Designed not to need an internet connection, so it will work anytime and anywhere you need it.

Great tool for pilots, drag racers, engine tuners, golfers, or anyone who needs to conveniently find their Density Altitude, Altimeter Setting, Relative Aid Density (RAD), Specific Humidity or Absolute Pressure.

No ads or in-app purchases.

We love feedback! Email us at

What’s New

Version 2.4

- New Sharing option in Settings
- New Animations added in transitions
- Other minor updates
Reach me anytime at Follow us on Instagram and Facebook @rateofclimbindustries

Ratings and Reviews

4.9 out of 5
571 Ratings

571 Ratings

Farabaugh ,

Works well

Wanted something to quickly calculate DA so I could input into my ballistics shooting app. I know this is designed for pilots but I thought it worth the try. Non humid days, works well. High humidity it’s off. I know this app uses dry air formula so not knocking the app. Developer did mention other possible uses tho.
To be able to manually enter values by turning off an automatic fill button would be great.

DA is becoming a more widely used method on ballistic applications over the previous idea of entering elevation and temperatures.

jway069 ,

Awesome developer!!!

Ok so the fact that they added stuff for racers when someone asked is awesome! Only thing I would like to see is the barometric pressure. Other than that this app is pretty sweet. I’m a racer BTW

RF219 ,

Great app

I really like this app. It works pretty good against my kestrel hand held weather station. I would like to see a tab for water grains in the air for the guys using it for drag racing

Developer Response ,

Thanks for the feedback! Good idea! I've added water grains now as well as Dyno Correction. It's in the 2.1 update. Thanks!

App Privacy

The developer, Rate Of Climb Industries, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy.

Data Not Collected

The developer does not collect any data from this app.

Privacy practices may vary, for example, based on the features you use or your age. Learn More


  • Family Sharing

    With Family Sharing set up, up to six family members can use this app.

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