Upcoming Changes to Thermo-Calc Compatibility with Mac

Last Updated: September 28, 2026

Two changes are coming that will affect compatibility between Thermo-Calc and Mac computers and may prevent you from running certain versions of Thermo-Calc on your Mac computer:

Thermo-Calc 2027a, scheduled for January 2027, will run directly on Macs with Apple silicon, without requiring Rosetta. Previously, Thermo-Calc ran directly on Intel-based Macs. As a result of this change, we expect Thermo-Calc 2027a to run significantly faster than earlier releases running through Rosetta. However, Thermo-Calc 2027a will not run on Intel-based Macs.

Beginning with macOS 28, scheduled for fall 2027, Apple will end general Rosetta support. As a result, Thermo-Calc 2026b and earlier releases will not run on Apple silicon Macs with macOS 28.

If you have a Mac with Apple silicon (M1, M2, M3, or later):

Beginning with Thermo-Calc 2027a, you will no longer need Rosetta to run Thermo-Calc. This change is expected to bring a significant speed improvement compared with earlier releases running through Rosetta.
Thermo-Calc 2026b and earlier versions will still require Rosetta. If it is not already installed on your computer, you will need to install it to run those releases on a compatible macOS version.
If you plan to continue using Thermo-Calc 2026b or earlier, do not upgrade to macOS 28 as those releases will no longer run. You can continue using them through Rosetta on compatible earlier macOS versions.
Before upgrading to macOS 28, confirm that your Thermo-Calc release supports it. Thermo-Calc 2027a removes the need for Rosetta, but compatibility with macOS 28 must be confirmed separately. Check our Roadmap for Platform Support before upgrading.

If you have an Intel-based Mac:

Thermo-Calc 2027a will not run on Intel-based Macs. To use Thermo-Calc 2027a on a Mac, you will need a Mac with Apple silicon.
You can continue using earlier compatible Thermo-Calc releases, provided your license remains valid, and your operating system remains compatible.

Not sure which Mac you have?

Open the Apple menu and select About This Mac. If you see Chip followed by an Apple chip name, such as Apple M1, you have a Mac with Apple silicon. If you see Processor followed by an Intel name, you have an Intel-based Mac.

Why is this Changing?

Thermo-Calc releases before 2027a were built for Intel-based Macs. On Macs with Apple silicon, users can install Rosetta, which translates software built for Intel processors so that it can run on Apple silicon. Apple has said that general Rosetta support will remain available through macOS 27 but will end with the following macOS release.

Moving Thermo-Calc to native Apple silicon aligns us with Apple’s future direction for Mac computers. It removes Thermo-Calc’s dependency on Rosetta and allows Thermo-Calc 2027a and later releases to run directly on Macs with Apple silicon. We will continue to test compatibility with individual macOS versions, so please check the Roadmap for Platform Support before updating your operating system.

Roadmap for Platform Support

System Requirements