An inexpensive, open-source alternative to the traditional Calculus textbook.

Version 3.0 is released! See Features page to learn more, including information about the interactive, 3D graphics.

APEX Calculus is a calculus textbook written for traditional college/university calculus courses. It has the look and feel of the calculus book you likely use right now (Stewart, Thomas & Finney, etc.). The explanations of new concepts is clear, written for someone who does not yet know calculus. Each section ends with an exercise set with ample problems to practice & test skills (odd answers are in the back). 

APEX Calculus looks like a "regular" calculus book in most all respects except the price. Anyone can download the .pdf version of the text for free. Want a print copy? Feel free to print it yourself, or buy a b&w copy from for $13. 

While APEX Calculus looks like an inexpensive version of the traditional calculus text, a closer look will show it's a better calculus book for an even better price. Check out the comparison section for more details.

Got questions? Explore the site, including the Frequently Asked Questions section. If you still need more information, just ask!