When doing replacement or upgrading on 2009 – 2018 Mazda 3 Sport with capsule halogen headlamps HID, the bulb size guide is necessary for you to take the reference.
Jump to corresponding car model with the catalog bellow.

Low Beam Headlight 2010 – 2018 H11
2009 H7
High Beam Headlight 2009 – 2018 9005
Back Up Light 2009 – 2018 7440
Brake 2010 – 2018 7443
Daytime Running Light 2010 – 2013 7443
2014 – 2018 9005
Dome Light 2009 – 2018 DE3175
Front Side Marker 2009 1157NA
2014 – 2018 12396NA
2010 – 2013 7444NA
Front Turn Signal 2009 1157
2014 – 2018 7440NA
2010 – 2013 7443NA
License Plate 2010 – 2013 12961
2009, 2014 – 2018 194
Parking Light 2009 1157
2014 – 2018 12396NA
2010 – 2013 12961
Rear Side Marker 2010 – 2018 7443
Rear Turn Signal 2010 – 2013 7440
2014 – 2018 7440NA
Tail Light 2010 – 2018 7443
Luggage Compartment 2010 – 2018 DE3022
Center High Mount Stop Light 2010 – 2013 921
Map Light 2009 12961
2010 – 2018 DE3175
Low Beam Headlight 2009 D2S
High Beam Headlight 2009 9005
High Beam and Low Beam Headlight 2010 – 2013 D2S
2014 – 2016 D4S
Front Fog Light 2014 – 2016 H8/H11/H16
Back Up Light 2009 – 2016 7440
Daytime Running Light 2010 – 2013 H8
Dome Light 2009 – 2016 DE3175
Front Side Marker 2009 1157NA
2014 – 2016 194
2010 – 2013 7444NA
Front Turn Signal 2009 1157
2014 – 2016 7440NA
2010 – 2013 7444NA
License Plate 2010 – 2013 12961
2009, 2014 – 2016 194
Parking Light 2009 1157
2010 – 2013 194
Rear Turn Signal 2010 – 2016 7440NA
Luggage Compartment 2010 – 2016 DE3022
Map Light 2009 12961
2010 – 2016 DE3175