Finding a "free product key" for professional software like Grapher 14 (developed by Golden Software) is highly risky and generally discouraged. Most sites promising free keys for high-end scientific software are scams that distribute malware or ransomware. 

If you're looking for affordable options to access Grapher 14, consider:

(a scientific graphing software by Golden Software) available for download. Product keys are unique identifiers provided only upon purchase or through official channels. Golden Software

Grapher 14 is a graphing and data visualization software developed by Golden Software. It's widely used in various fields, including science, engineering, education, and business. The software offers a range of features, including: