Fluid heater of the flow-heater type, comprising: a fluid channel with at least one first fluid channel section (135; 235), at least one substantially cylindrical metal pipe, preferably made of a stainless steel and particularly preferably with a diameter of 10 mm to 20 mm as well as a length of 120 mm to 220 mm, a heating device with at least one tubular heating body, preferably with at least two tubular heating bodies (6a, 6b), spaced apart from each other over equidistant circumferential sections of the metal pipe and heat conducting means for distributing the heat from the heating device to regions of the metal pipe in contact with the heat conducting means, a fluid-guiding core (130; 230), preferably made from a plastic, which is arranged in the metal pipe and which forms the first fluid channel section (135; 235) between the metal pipe and the fluid-guiding core (130; 230), and a first fluid connection for fluid supply means and a second fluid connection for fluid removal means, which are connected to respective ends of the fluid channel, wherein the first fluid channel section runs substantially helically in the form of a groove in an outer surface of the fluid-guiding core and the first fluid channel section forms a flow path for the fluid with a hydraulic length, which is preferably about double, particularly preferably at least about three times as long as the length of the metal pipe, and wherein the fluid-guiding core (130; 230) has at least one substantially conical end (131b; 231b), which has a fluid channel end section (136, 137; 236, 237) configured in the form of a substantially bend-free extension of the first fluid channel section (135; 235) and opening out on the front face of the conical end (131b; 231b). a fluid channel with at least one first fluid channel section (135; 235), at least one substantially cylindrical metal pipe, preferably made of a stainless steel and particularly preferably with a diameter of 10 mm to 20 mm as well as a length of 120 mm to 220 mm, a heating device with at least one tubular heating body, preferably with at least two tubular heating bodies (6a, 6b), spaced apart from each other over equidistant circumferential sections of the metal pipe and heat conducting means for distributing the heat from the heating device to regions of the metal pipe in contact with the heat conducting means, a fluid-guiding core (130; 230), preferably made from a plastic, which is arranged in the metal pipe and which forms the first fluid channel section (135; 235) between the metal pipe and the fluid-guiding core (130; 230), and a first fluid connection for fluid supply means and a second fluid connection for fluid removal means, which are connected to respective ends of the fluid channel, wherein the first fluid channel section runs substantially helically in the form of a groove in an outer surface of the fluid-guiding core and the first fluid channel section forms a flow path for the fluid with a hydraulic length, which is preferably about double, particularly preferably at least about three times as long as the length of the metal pipe, and wherein the fluid-guiding core (130; 230) has at least one substantially conical end (131b; 231b), which has a fluid channel end section (136, 137; 236, 237) configured in the form of a substantially bend-free extension of the first fluid channel section (135; 235) and opening out on the front face of the conical end (131b; 231b).