Northern Ireland is about 1.4 times bigger than Big Island of Hawaii.

Big Island of Hawaii is approximately 10,434 km² (4,029 sq mi), while Northern Ireland is approximately 14,130 km² (5,456 sq mi), making Northern Ireland 35% larger than Big Island of Hawaii.
Tip: This to-scale comparison of Big Island of Hawaii vs. Northern Ireland uses the Mercator projection, which distorts the size of regions near the poles.
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