In this paper, attenuators with distributed resistor networks for attenuation up to 30dB from DC to 25GHz are presented. The distributed thin-film resistor network is embedded in coplanar waveguide (CPW) for microwave application. The sheet resistance and size of distributed thin-film resistor network are accurately calculated by conformal mapping and elliptic function for corresponding attenuation. The achieved attenuators is based on the use of tantalum-nitride (TaN) thin-film resistors with low mean temperature coefficient of resistance (TCR), high resistance silicon substrate and Au CPW. Microwave testing results show excellent performance with return losses better than 27dB and insertion losses of 10.23 ± 0.12dB, 15.23 ± 0.18dB, 20.09 ± 0.23dB and 29.17 ± 0.55dB in the interesting frequency range.