Strange so much arguing with no data presented or sourced.
IMF US 18.6 EU 16.4 China 11.2
World Bank US 18.6 EU 16.4 China 11.2
UN US 18.0 EU 16.8 China 11.2
All figures nominal GDP, US$, trillions, 2016, per https://en.wikipedia.org/wiki/List_of_countries_by_GDP_(nomi...
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Things are a bit different when switching to PPP though.
IMF (2017) China 23.2 EU 20.9 US 19.4
World Bank (2016) China 21.4 EU 19.7 US 18.6
CIA (2016) China 21.1 EU 20.0 US 18.6
All figures nominal GDP, US$, trillions, per https://en.wikipedia.org/wiki/List_of_countries_by_GDP_(PPP)