A battery-powered portable tool, such as a chainsaw, hedge trimmer or handheld drill, comprising: a housing (1), a driven element (2) supported by the housing (1), an electric motor (6) coupled to the driven element (2) so as to drive the driven element (2), a battery (5) electrically coupled to the motor (6) so as to supply electric current to the motor (6) and a control circuit (8) arranged to control the supply of electric current to the motor (6) from the battery (5), in which the control circuit (8) comprises a main switch (8) operable by a user and an auxiliary switch (10, 11) also operable by a user; in which the control circuit (8) has: an active state in which operation of the main switch (8) by the user allows electric current to flow to the motor (6) so as to cause the driven element (2) to be driven; and an inactive state in which operation of the main switch (8) does not allow electric current to flow to the motor (6) and so the motor (6) does not drive the driven element (2); in which operation of the auxiliary switch (10, 11) causes the control circuit (8) to change between the active and inactive states; and in which the control circuit is further provided with indication means (30) arranged to provide an indication to a user whether the control circuit (8) is in the active or inactive mode. The indication may be by the means of light emitting devices (31, 32) or a speaker (33); user-uploadable sounds may be stored in a memory (34) of the tool to enable a user to customise the sound of their tool.