Lake Erie is about 1.8 times bigger than Northern Ireland.

Northern Ireland is approximately 14,130 km² (5,456 sq mi), while Lake Erie is approximately 25,744 km² (9,940 sq mi), making Lake Erie 82% larger than Northern Ireland.
Tip: This to-scale comparison of Northern Ireland vs. Lake Erie uses the Mercator projection, which distorts the size of regions near the poles.
Our free app, MapSize by MyLifeElsewhere — compare any two places, to scale on your mobile device.