An automatic sealing machine for the automatic sealing of the peripheral cavity of an insulating glass (1, 1', 1", 1′′′) with a secondary sealant (5, 5', 5"), the insulating glass having a geometry being irregular for the planarity with regard to the theoretical one, consisting of at least two glass panes (2, 2', 2", 2′′′ etc.) having rectangular or other than rectangular shape and at least one spacer frame (3, 3', 3" etc., 4, 4', 4" etc.) located in proximity of the perimeter at a finite distance from the boundary of the same glass panes if aligned or of a smaller glass pane if stepped, the glass panes being stepped along one or more or all peripheral sides of the insulating glass and the thickness both of each glass pane (2, 2', 2", 2′′′ etc.) and of the at least one spacer frame (3, 3', 3" etc., 4, 4', 4" etc.) and consequently the total thickness of the insulating glass (1, 1', 1", 1′′′) being mutable from insulating glass to insulating glass, said automatic sealing machine comprising: at least one synchronous conveyor having the function of support and displacement, together with a synchronous suction cup carriage of the machine, of the insulating glass (1, 1', 1", 1′′′) along a horizontal axis during the sealing cycle; at least a synchronous carriage with a chassis able to run on vertical rails (202a, 202b) of the machine along a pseudo-vertical axis carrying a sealing head, said pseudo-vertical axis being slightly inclined with respect to the vertical by an angle (α), said sealing head having a registering motion along a transverse axis slightly inclined with respect to the horizontal by an angle (α) and orthogonal to the insulating glass (1, 1', 1", 1′′′) to adapt to the thicknesses of the components of the insulating glass (1, 1', 1", 1′′′) and to follow the non planarity of the glass panes (2, 2', 2", 2"' etc.) composing the insulating glass (1, 1', 1", 1′′′) and a rotational synchronous motion (Θ) so that a sealing nozzle of the sealing head can be oriented lying tangent to the perimeter of the insulating glass (1, 1', 1", 1′′′), or anyhow a relative movement between the insulating glass (1, 1', 1", 1′′′) and the sealing nozzle being able to take place through different mechanisms and the insulating glass layout being any, whereby the sealing nozzle can be fed by one or more, in case of multiplicity of types of secondary sealants (5, 5', 5"), synchronous volumetric dosing units assemblies of the machine, whereby the sealant can be a bi-component or mono component sealant compound; each volumetric dosing unit assembly being constituted: for the bi-component case, by a dosing unit for a base compound and by a dosing unit for a catalyst compound, for the mono-component case by a single dosing unit, which respective flow rates can be controlled in function: a) of stoichiometric dosing ratio, in the case of the bi-component compound; b) of the dimensions of the peripheral cavity of a peripheral edge defined between the glass panes (2, 2', 2", 2′′′ etc.) and the extrados of the spacer frame (3, 3', 3" etc., 4, 4', 4" etc.); and c) of the relative speed between the nozzle and the perimeter of the insulating glass (1, 1', 1", 1′′′), so that to fill the cavity until the extreme edge of the smaller glass pane if stepped or of the same glass panes if aligned; the automatic sealing machine further comprising a controller logically interlacing all the above components of the automatic sealing machine; wherein the automatic sealing machine further comprises the following devices, all located in the synchronous carriage: an actuator; mechanical transmissions (502, 503); a support; a pneumatic cylinder/compensator; a joint with a carriage; a transducer, wherein the automatic sealing machine further comprises a sensor located in the sealing head, characterized by the fact that said devices and sensor are interfaced among them and can operate in connection with the location of the peripheral cavity of the insulating glass (1, 1', 1", 1′′′) allowing the sealing nozzle to follow, without solution of continuity, not the theoretical location but the real location of said cavity, along the transverse axis, different from the theoretical one due to the non planarity of the insulating glass (1, 1', 1", 1′′′), with control of position and with control of the force performed by the nozzle against the inner face of the bigger glass pane in the positions of the perimeter of the insulating glass where the glass panes are stepped.