Vietnam is approximately 331,210 sq km, while Cambodia is approximately 181,035 sq km, making Cambodia 54.66% the size of Vietnam. Meanwhile, the population of Vietnam is ~98.7 million people (81.8 million fewer people live in Cambodia).
This to-scale map shows a size comparison of Vietnam compared to Cambodia. For more details, see an in-depth quality of life comparison of Cambodia vs. Vietnam using our country comparison tool.