Examples disclosed herein relate to performing an action based on a pre-boot measurement of a firmware image. In an example, at a firmware component in a system, a measurement of a firmware image may be determined prior to booting of the system, beginning from a hardware root of trust boot block, by a Trusted Platform Module (TPM) emulator engine that emulates a hardware-based TPM. A pre-determined measurement of the firmware image may be retrieved from a storage location within the system. The measurement of the firmware image may be compared with the pre-determined measurement of the firmware image prior to booting of the system. In response to a determination that the measurement of the firmware image is different from the pre-determined measurement of the firmware image, performing an action.