Prince Edward Island is about 2.5 times smaller than Northern Ireland.

Northern Ireland is approximately 14,130 km² (5,456 sq mi), while Prince Edward Island is approximately 5,620 km² (2,170 sq mi), making Prince Edward Island 39.77% the size of Northern Ireland.
Tip: This to-scale comparison of Northern Ireland vs. Prince Edward Island uses the Mercator projection, which distorts the size of regions near the poles.
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