AGN surface density versus survey area comparison for a number of wide field and medium area surveys in different wavebands. Included AGN surface densities are: EWS detectable AGN (magenta diamond, unfilled), EWS selected AGN (magenta diamond, solid fill), EWS selected AGN using Euclid photometry only (magenta diamond, translucent fill), EDS detectable AGN (blue diamond, unfilled), EDS selected AGN (blue diamond, solid fill), EDS selected AGN using Euclid photometry only (blue diamond, translucent fill), XMM-SERVS (black downward-facing triangle, unfilled), XXL-3XLSS (black cross, unfilled), eFEDS (black square, unfilled), eRASS1 (black pentagon, unfilled), DES (green circle, unfilled), SDSS spectroscopic lower limit (green lower limit), Spitzer Space Telescope combined cryogenic surveys (red plus, unfilled), AllWISE R90 selection (red left-facing triangle, unfilled), and AllWISE C75 selection (red right-facing triangle, unfilled). The considered Euclid detectable AGN have ≥5σ detection in at least one Euclid band. The plotted values and references for each survey are given in Table 7.