# CMAKE_TLS_VERSION

Added in version 3.30.

Specify the default value for the `file(DOWNLOAD)` and `file(UPLOAD)` commands' `TLS_VERSION` option. If this variable is not set, the commands check the `CMAKE_TLS_VERSION` environment variable. If neither is set, the default is TLS 1.2.

Changed in version 3.31: The default is TLS 1.2. Previously, no minimum version was enforced by default.

The value may be one of:

- `1.0`

- `1.1`

- `1.2`

- `1.3`

This variable is also used by the `ExternalProject` and `FetchContent` modules for internal calls to `file(DOWNLOAD)` and `git clone`.