For EUV-lithography, reliable measurements of the radiant power throughout the optical chain are an essential requirement for the optimization of the lithographic production process as well as for the development of new applications like EUV-based metrology tools. From dose control to aerial imaging, specialized detectors are required - ranging from simple diodes to sophisticated imaging detectors like CCD or CMOS systems. For all these applications, sensitivity, homogeneity and lifetime are crucial parameters. While extended lifetime and sub percent homogeneity requirements are common among all detector uses, sensitivity targets range from single photon sensitivity for spectroscopy detectors to deliberately reduced sensitivity for dose control at high-power sources. Photon detector calibration in the EUV spectral range is therefore a prerequisite for new detector developments and a basis for the introduction of EUV-lithography into volume manufacturing. PTB employs two dedicated and complimentary EUV beamlines for radiometric characterizations of photon detectors. The wavelength range covered reaches from below 1 nm to 45 nm for the two EUV beamlines. Longer wavelengths coverage in the VUV range (out-of-band) is provided at PTB’s VUV radiometry beamline. The standard spot size is 1 mm by 1 mm with an option to go as low as 0.1 mm by 0.1 mm. For lifetime testing, a dedicated exposure setup with power densities of up to 20 W/cm2 is operated. It enables exposures in the range of 100 kJ/cm2 within a reasonably short time. Lower fluence levels are available by attenuation or exposure farther out of focus. We will explain calibration basics, describe PTB's calibration capabilities in the EUV spectral range and show exemplary data for the respective detector types.