Standard exchange current densities (&,,) of various aqueous redox systems at platinum electrodes have been calculated from literature exchange current densities and their measured variation with concentration or electrode potential. Values for the systems Ce(IV)/Ce(III), Mn(IV)/ Mn(III), Mn(III)/Mn(II), TI(III)/Tl(I), Fe(III)/Fe(II), Fe(CN),"-/Fe(CN),"-, FeOx,3-/FeOx,4-, Cl.&-, Br,/Br-, Is-/I-, and quinone/hydroquinone have been listed and compared. The Br,/Brcouple has the largest value of ioo, 40 A/cmZ. R&m&-On dCduit des don&es bibliographiques et de nouvelles mesures les densites de courant d'Cchange standard i,, pour divers systbmes rbdox, en solution aqueuse avec Electrode Pt. L'on classe ainsi les systkmes Ce(IV/Ce(III); Mn(IV)/Mn(II); Mn(III)/Mn(II); Tl(III)/(TII), Fe(III)/ Fe(II); Fe(CN),Sm/Fe(CN),4m; FeOxSS-/FeOx,*-; Cl,/Cl-; Br,/Br-; 1,-/I-; quinone hydroquinone. La plus grande valeur i,, = 40 A/cm2 a &5. trouvee pour Br,/Br-. Zusammenfassung-Die Standardaustauschstromdichten (ioo) bei Platinelektroden sind fiir die Systeme Ce(IV)/Ce(III), Mn(IV)/Mn(III), Mn(III)/Mn(II), Tl(III)/TI(I), Fe(III)/Fe(II), Fe(CN),*-/ Fe(CN),4-, FeOx,S-/FeOx,4-, Cl&Y, Br,/Br-, Is-/I-, und Chinon/Hydrochinon in wlssrigen Ltisungen aus den Literaturaustauschstromdichten und ihrer Konzentrations-bzw. Potentialabhgngigkeit berechnet worden. Das Br,/Brr System zeigt den hiichsten Wert, ioo = 40 A/cm2.