Cutting or compression tool, comprising: - a housing and a driving group (5,6,7,8,11) connected to the housing and configured to move a driving piston with respect to the housing, - a fixed jaw which forms a first connecting seat for a first connection pivoted at a first connection point and a second connecting seat for a second connection pivoted at a second connection point, wherein the second connecting seat is spaced from the first connecting seat and the fixed jaw is stationarily connected with respect to the housing through said first and second connecting seat, - a mobile jaw which forms a first fulcrum seat for a first hinged connection and a second fulcrum seat for a second hinged connection, wherein the second fulcrum seat is spaced from the first fulcrum seat and the mobile jaw is hinged to the fixed jaw through the first fulcrum seat at a first fulcrum point, wherein the second connection point of the fixed jaw coincides with the first fulcrum point of the mobile jaw, characterized by further comprising - a first connecting rod having a first end hinged to the driving piston and a second end hinged to the mobile jaw through the second fulcrum seat at a second fulcrum point, so that, in response to the movement of the driving piston with respect to the housing, the mobile jaw and the fixed jaw perform a relative rotational movement about the first fulcrum point, between an open position and a closed position in order to perform the cutting or the compression, wherein the distance between the first connecting seat and the second connecting seat of the fixed jaw is equal to the distance between the first fulcrum seat and the second fulcrum seat of the mobile jaw, - a second connecting rod having a first end pivoted to the housing at a third connection point and a second end pivoted to the fixed jaw through one of the first and second connecting seats, and wherein the fixed jaw is further directly pivoted to the housing through the other one of the first and second connecting seats, so that the housing, the connecting rod and the fixed jaw form an articulated non-deformable triangle. - a housing and a driving group (5,6,7,8,11) connected to the housing and configured to move a driving piston with respect to the housing, - a fixed jaw which forms a first connecting seat for a first connection pivoted at a first connection point and a second connecting seat for a second connection pivoted at a second connection point, wherein the second connecting seat is spaced from the first connecting seat and the fixed jaw is stationarily connected with respect to the housing through said first and second connecting seat, - a mobile jaw which forms a first fulcrum seat for a first hinged connection and a second fulcrum seat for a second hinged connection, wherein the second fulcrum seat is spaced from the first fulcrum seat and the mobile jaw is hinged to the fixed jaw through the first fulcrum seat at a first fulcrum point, - a first connecting rod having a first end hinged to the driving piston and a second end hinged to the mobile jaw through the second fulcrum seat at a second fulcrum point, - a second connecting rod having a first end pivoted to the housing at a third connection point and a second end pivoted to the fixed jaw through one of the first and second connecting seats, and