External-cavity diode lasers are ubiquitous in atomic physics and a wide variety of other scientific disciplines, due to their excellent affordability, coherence length, and versatility. However, for higher-power applications, the combination of seed lasers, injection-locking and amplifiers can rapidly become expensive and complex. Here we present a high-power, single-diode laser design with specifications: textgreater 210 m W , 100 ms-linewidth ( 427 ± 7 ) k H z , textgreater 99 % mode purity, 10 GHz mode-hop-free tuning range, and 12 nm coarse tuning. Simple methods are outlined to determine the spectral purity and linewidth with minimal additional infrastructure. The laser has sufficient power to collect 10 10 87 R b atoms in a single-chamber vapor-loaded magneto-optical trap. With appropriate diodes and feedback, the system could be easily adapted to other atomic species and diode laser architectures.