Air Density Online

weather calculations for racing engine tuning


Jet your car from anywhere with an internet connection. Have a smartphone? You now have a portable jetting calculator.

for tracks

Real-time density altitude from current weather data at various tracks including: NHRA & IHRA dragstrips, road courses, dirt ovals.


Get your MFI fuel system setup programmed into ProCalc. Even get your dyno data added. You get 1 year of access to ProCalc too!

Thanks for visiting our site. We provide real-time, historical, and forecast weather data for racing engine tuning. We also provide engine tuning tools for mechancial fuel injected racing engines. We are constantly adding tracks to the site. If you'd like to see your track added to the list, send it over. Learn more about this site and it's creators or read some of the articles we've written.

What's New

June 1, 2023

Recent site updates

Summer is coming and we hope to have our weather situation all sorted out now. While we appreciate the emails we've received we have been dealing with numerous problems outside of our control when it comes to weather API's. However we hope it's working well now.

Here are the tracks we've added recently. If you don't see your track listed here, let us know and we'll add it.

April 23, 2023

Weather Woes

With the recent closing of Dark Sky, we have had to find another weather provider for the free race track weather section of the site. Unfortunately, we are running into some difficulties with our other options. We appreciate your patience while we get these problems worked out.

April 4, 2023

Effects of Humidity on Tuning

Our latest article is up on

Effects of Humdiity on Tuning and Traction

Check it out!

view news archive

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