Transparent-photochromic　materials　have　garnered　significant　attention　for　their　applications　in　optical　information　storage　and　anti-counterfeiting,　which　necessitate　excellent　transparency　and　high　optical　contrast.　Herein,　x　mol%　Sr2+　and　1　mol%　Ho3+-codoped　(K0.5Na0.5)NbO3　(xSr-1Ho-KNN)　ceramics　were　synthesized　by　a　conventional　solid-state　reaction　and　pressureless　sintering.　Notably,　the　7Sr-1Ho-KNN　ceramic　displays　exceptional　transmittance　(60.7%　at　780　nm),　attributed　to　its　fine　grains　and　highly　symmetric　crystal　structure.　The　photochromic　(PC)　contrast　based　on　the　change　in　photoluminescence　(PL)　intensity　of　7Sr-1Ho-KNN　under　excitation　with　a　980　nm　laser　reaches　as　high　as　91.5%.　After　thermal　treatment　under　appropriate　conditions,　the　transmittance　and　PL　intensity　of　the　ceramic　can　revert　to　their　respective　original　values,　demonstrating　superior　optical　stability　in　response　to　alternating　light　and　thermal　stimuli.　The　combination　of　high　transparency　and　PC　contrast　suggests　that　the　xSr-1Ho-KNN　ceramics　have　promising　potential　for　optical　information　storage　and　optical　anti-counterfeiting　applications,　which　can　guide　the　development　of　other　KNN-based　materials　or　even　multifunctional　luminescent　ferroelectrics.　©　2025　The　Royal　Society　of　Chemistry.