What voltage does the Creality Ender-3 run at?
Bearing in mind that the specifications on Amazon's page are sometimes not 100% (even though they are in this case), it is always best to check on the manufacturer's website.
From Creality3D's own website, Creality3D.shop, on the Creality3D Ender-3 product page, Creality3D Ender-3 3D Printer Economic Ender DIY KITS, the specifications are given as (emphasis is mine):

##ender-3 Machine Parameter:

Modeling Technology：FDM (Fused Deposition Modeling）
Printing Size：220220250mm
Machine Size：440410465mm
Package weight：8kg Max
Traveling Speed：180mm/s
Filament：1.75mm PLA,TPU,ABS
Input：AC 100-265V 50-60Hz
Output：DC 24V 15A 360W
Layer Thickness：0.1-0.4mm
Nozzle diameter：0.4mm
Precision：±0.1mm
File Format：STL,OBJ,G-Code
Working Mode：Online or SD offline
Max Nozzle Temperature：255℃
Max Hot bed Temperature：110℃