Mixer device for a gas burner having a housing which has a combustion air inlet, a gas inlet and an outlet for the mixture of gas and combustion air, and having a Venturi device positioned in the housing, which is used to mix the combustion air and the gas, the Venturi device being contoured, forming a tapering contraction section, a mixing section and a widening diffuser section, in such a way that starting from the combustion air inlet, the combustion air can be fed to the mixing section via the contraction section tapering in the direction of the mixing section, and that starting from the mixing section, the mixture of gas and combustion air can be fed to the outlet via the widening diffuser section, the mixing section of the Venturi device having multiple annular gap-like nozzle sections, the Venturi device being assembled from an inlet funnel and an outlet funnel, the multiple annular gap-like nozzle sections forming multiple partial mixing sections, via which the gas can be mixed with the combustion air, each of the multiple partial mixing sections having a smaller diameter (d 23) and cross section than the mixing section of the Venturi device assembled from the same, and each of the partial mixing sections of the Venturi device having a partial contraction section arranged upstream and a partial diffuser section arranged downstream, forming a multiplicity of partial Venturi devices, each partial contraction section having a smaller diameter and cross section than the tapering contraction section assembled from the same, and each partial diffuser section having a smaller diameter and cross section than the widening diffuser section assembled from the same, characterized in that the mixing section, in which gaps are formed between the inlet funnel and the output funnel, forms multiple annular gap-like nozzle sections. having a housing which has a combustion air inlet, a gas inlet and an outlet for the mixture of gas and combustion air, and having a Venturi device positioned in the housing, which is used to mix the combustion air and the gas, the Venturi device being contoured, forming a tapering contraction section, a mixing section and a widening diffuser section, in such a way that starting from the combustion air inlet, the combustion air can be fed to the mixing section via the contraction section tapering in the direction of the mixing section, and that starting from the mixing section, the mixture of gas and combustion air can be fed to the outlet via the widening diffuser section, the mixing section of the Venturi device having multiple annular gap-like nozzle sections, the Venturi device being assembled from an inlet funnel and an outlet funnel, the multiple annular gap-like nozzle sections forming multiple partial mixing sections, via which the gas can be mixed with the combustion air, each of the multiple partial mixing sections having a smaller diameter (d 23) and cross section than the mixing section of the Venturi device assembled from the same, and each of the partial mixing sections of the Venturi device having a partial contraction section arranged upstream and a partial diffuser section arranged downstream, forming a multiplicity of partial Venturi devices, each partial contraction section having a smaller diameter and cross section than the tapering contraction section assembled from the same, and each partial diffuser section having a smaller diameter and cross section than the widening diffuser section assembled from the same, characterized in that the mixing section, in which gaps are formed between the inlet funnel and the output funnel, forms multiple annular gap-like nozzle sections. starting from the combustion air inlet, the combustion air can be fed to the mixing section via the contraction section tapering in the direction of the mixing section, and that starting from the mixing section, the mixture of gas and combustion air can be fed to the outlet via the widening diffuser section, the mixing section of the Venturi device having multiple annular gap-like nozzle sections, the Venturi device being assembled from an inlet funnel and an outlet funnel, the multiple annular gap-like nozzle sections forming multiple partial mixing sections, via which the gas can be mixed with the combustion air, each of the multiple partial mixing sections having a smaller diameter (d 23) and cross section than the mixing section of the Venturi device assembled from the same, and each of the partial mixing sections of the Venturi device having a partial contraction section arranged upstream and a partial diffuser section arranged downstream, forming a multiplicity of partial Venturi devices, each partial contraction section having a smaller diameter and cross section than the tapering contraction section assembled from the same, and each partial diffuser section having a smaller diameter and cross section than the widening diffuser section assembled from the same,