Atmosculator is a freeware Mac OS X application that calculates key properties of the Earth's atmosphere as a function of altitude using the 1976 Standard Atmosphere Model. It can be used to determine the pressure, temperature, density, viscosity and other parameters up to an altitude of 278,385 feet (84.852 km). The 1976 model is the latest of a number of versions developed jointly by NOAA, NASA and the USAF. The complete model includes properties at even higher altitudes, but these regions are more complex and are not included here.

Atmosculator also provides the option of calculating properties under non-standard conditions - i.e. when the temperature differs from that of the standard model.

Although the values provided by Atmosculator have been carefully checked against the original U.S. Government source, their accuracy cannot be guaranteed, so please use this tool at your own risk.

(If the above link does not work, try: U.S. Standard Atmosphere 1976 which can be found by searching NASA Technical Reports Server. This link might be useful: U.S. Standard Atmosphere 1976.)

Atmosculator includes extensive Help on the basis of the model and a mathematical derivation showing how the properties are calculated. For your online convenience, this description of the Standard Atmosphere Model is reproduced here.



Download v3.0 as:

Zip Archive

1) None - see version history below

Version History:

For v2.02:

  • In the documentation under Help, the sign of the lapse rate for layer 6 in the table titled "Definition of Layers in Model" was incorrect in v2.01; it used to indicate an inversion; v2.02 shows the correct negative value. The lapse rate actually used in the model calculations was correct for both v2.01 and v2.02. Thanks to Dr. Pasquale Sforza for catching this.

For v2.03:

  • A typo has been fixed in the units popup for kinematic viscosity: the metric units label now reads m^2/s instead of m^s/s (the numerical values remain unchanged). Thanks to Stefano Paris for catching this.
  • The text that appears in Help Viewer has been reduced to a more suitable size
  • The expiration dialog will show the correct version when it appears in 2008 (the expiration dialog for v2.02 incorrectly said that v2.01 has expired)
  • The app now displays correct version info in the Finder

For v2.04:

  • The application will now expire gracefully; it will warn of pending expiration once per day starting 28 days from expiration, and when the expiration date has been passed, the user will have the option to either quit or continue
  • Minor changes to Help

Note that 2.04 is a PPC-only version but should work correctly on any Intel Mac that has Rosetta.
Apple discontinued Rosetta with the release of OS X 10.7 so you cannot use v2.04 on this or later versions of OS X.

For v3.0β:

  • The first Intel-native release; it should run on any Mac with an Intel processor running OS X 10.7 or later.
    It has been released as a beta with a 3 month expiration (good until 2/28/15) so you can help with testing.
    If any problems are found during this period, I will include fixes in the official 3.0 release early in 2015
  • A sign error in Atmosculator's built-in documentation, has been fixed. The sign used in front of the h in the numerical solutions should have been - not + for the altitudes between 167,323 and 232,940 ft and also between 232,940 and 278,386 ft. Please see this ERRATA for the online documentation. Thanks to R. Wayne Wilson for catching this.
  • A typo in the formula for the gas constant in Atmosculator's built-in documentation has been fixed. Under Gas Properties, the equation for the Specific Gas Constant in terms of the Universal Gas Constant should read R = R*/M and not R = R*·M. Please see this ERRATA for the online documentation. Thanks to Quentin Minster for catching this.

For v3.0:

  • No problems were reported so this is the same as 3.0β without the β and with the expiration extended until 6/30/2016.


Simple mobile device-sized static table


If you have feedback, suggestions, questions, or would like to be notified when new versions are available:
info2 @ atmosculator . com




Copyright © 1991-2016, Graham Gyatt. All Rights Reserved.

Site last modified: June 20, 2016