We present a catalog of 535 fast radio bursts (FRBs) detected by the Canadian Hydrogen Intensity Mapping Experiment Fast Radio Burst (CHIME/FRB) Project between 400 and 800 MHz from 2018 July 25 to 2019 July 1, including 61 bursts from 18 previously reported repeating sources. The catalog represents the first large sample, including bursts from repeaters and non-repeaters, observed in a single survey with uniform selection effects. Through injection of simulated events into our detection pipeline, we perform an absolute calibration of selection effects. The catalog’s large sample and control of systematic biases enables precision characterization of the FRB population. Among other results, we find that bursts from repeating sources differ in burst morphology from apparent non-repeaters, find evidence for a large population of highly scattered events, and measure the fluence distribution and overall sky rate of the FRB population.