Mongolia is about 11 times bigger than Tajikistan.

Tajikistan is approximately 144,100 sq km, while Mongolia is approximately 1,564,116 sq km, making Mongolia 985% larger than Tajikistan. Meanwhile, the population of Tajikistan is ~10.8 million people (7.2 million fewer people live in Mongolia).
Tip: This to-scale comparison of Tajikistan vs. Mongolia uses the Mercator projection, which distorts the size of regions near the poles.
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