United Kingdom is approximately 243,610 sq km, while Singapore is approximately 719 sq km, making Singapore 0.3% the size of United Kingdom. Meanwhile, the population of United Kingdom is ~65.8 million people (59.6 million fewer people live in Singapore).
This to-scale map shows a size comparison of United Kingdom compared to Singapore. For more details, see an in-depth quality of life comparison of Singapore vs. United Kingdom using our country comparison tool.