Comparison of different survey-averaged eROSITA PSFs. Shown are the PSFs in the bands 0.2–2.3 keV (left panels), 2.3–5.0 keV (central panels), or for the individual TMs from stacking in 0.2–2.3 keV (right panels). The PSF models shown are the survey-averaged shapelet PSFs, those obtained by stacking sources (see text in Appendix A for more details) and those from ground-based measurements using PANTER. The top row of panels show the PSF surface brightness profiles, normalised within 4 arcmin radius, where the vertical lines plot the FWHM values. The second panels down show the fractional difference of the surface brightness of each PSF from the average stacked profile. The third panels down show the cumulative signal as a function of radius, plotting the HEWs as vertical lines. The lowest panels show the fractional difference of the cumulative profiles to the average stacked profile. The shapelet PSFs are those used for fitting the energy band given, the stacked PSF is weighted by the spectra of the input sources, and the PANTER PSF is obtained at the monochromatic energy specified, which is chosen to be representative of the source photons in the band. The shapelet PSF is plotted as a dashed line outside a radius of 1 arcmin, the maximum used for fitting in the source detection pipeline. In the two leftmost columns, the PSF images were rebinned with 4 arcsec pixels where necessary for a fair comparison. In the rightmost column, we show the best fitting model and uncertainties, rather than stacked, rescaled and rebinned count profiles. The FWHMs quoted are sensitive to the pixelisation used and the inner value, and so should be used with care. HEWs were computed from minimally-binned images.