Native Instruments is not available as a free standalone download for the full version . The "Full" version of Kontakt is a paid professional sampler. However, you can legally download and use the Kontakt Player , which is the free version of the software. Free vs. Paid Version
If you specifically need Kontakt 6 due to an older macOS (like 10.12–10.15), you may need to use Legacy Installers provided by NI support. System Requirements (v6.5.x) Installation and setup - Native Instruments Native Instruments Kontakt 6 v6.5.3 for Mac Free Download
Once logged in, go to the "Available" or "Library" section. Look for Kontakt Player (currently updated to version 8) and click Install . Native Instruments is not available as a free
Runs all official Native Instruments libraries and licensed third-party libraries. It is often included in the Komplete Start bundle . Free vs