2021 BMW i3 tire size

Most common factory size

P155/70R19

Tire sizes by trim

Source marks: one source

2021 BMW i3 tire size by trim
Size	Trims	Width, mm	Sidewall, % of width	Rim, in	Diameter, in	Sidewall, in	Revs per mile
P155/70R19	RWD, Base w/Range Extender RWD	155	70	19	27.54	4.27	732
P175/55R20	s RWD, s w/Range Extender RWD	175	55	20	27.58	3.79	731

What P155/70R19 means
Part	Number	Meaning
Type	P	Passenger car tire.
Width	155 mm	Tread width. 6.1 in.
Sidewall	70	Sidewall height is 70% of the width.
Construction	R	Radial tire.
Rim	19 in	Fits 19 in wheels.

Within 3% of the stock diameter. A common shop guideline, not a maker spec.

Sizes within 3% of P155/70R19
Size	Rim, in	Diameter, in	Change	Speedo reads at 60 mph
175/55R20	20	27.58	+0.1%	59.9 mph
275/35R20	20	27.58	+0.1%	59.9 mph
215/45R20	20	27.62	+0.3%	59.8 mph
245/50R18	18	27.65	+0.4%	59.8 mph
275/40R19	19	27.66	+0.4%	59.7 mph
245/45R19	19	27.68	+0.5%	59.7 mph
235/40R20	20	27.40	-0.5%	60.3 mph
245/40R20	20	27.72	+0.6%	59.6 mph

Sizes within 3% of P175/55R20
Size	Rim, in	Diameter, in	Change	Speedo reads at 60 mph
275/35R20	20	27.58	0.0%	60.0 mph
155/70R19	19	27.54	-0.1%	60.1 mph
215/45R20	20	27.62	+0.1%	59.9 mph
275/30R21	21	27.50	-0.3%	60.2 mph
275/40R19	19	27.66	+0.3%	59.8 mph
245/45R19	19	27.68	+0.4%	59.8 mph
245/40R20	20	27.72	+0.5%	59.7 mph
245/35R21	21	27.75	+0.6%	59.6 mph

Checked against 292 factory sizes listed for 2009-2027 US models.

Tire pressure is on the driver door sticker. Not in this data.

Optional wheel packages may differ.