Lato vs Arimo

Both are sans serif faces on Google Fonts. Arimo has the larger x-height, so it looks bigger at the same size. Lato takes more horizontal space.

Try your own text

Lato

Handgloves & Quartz Jockeys

The quick brown fox jumps over the lazy dog. Pack my box with five dozen liquor jugs, then ship it to 1,842 Grove Street by 9:30 AM.

Handgloves & Quartz Jockeys

The quick brown fox jumps over the lazy dog. Pack my box with five dozen liquor jugs, then ship it to 1,842 Grove Street by 9:30 AM.

Measured from the font files. Heights and widths are shown as a share of the font size, so they compare directly at any point size.
Measurement	Lato	Arimo	Difference
x-heightHeight of lowercase letters, as a share of the font size. Higher reads larger at the same point size.	50.6%	52.8%	2.2%
Cap heightHeight of capitals, as a share of the font size.	71.7%	68.8%	2.9%
x-height to cap ratioProportion of lowercase to uppercase. Higher feels more modern and open.	0.71	0.77	0.06
Stroke weightMeasured thickness of a vertical stroke. Higher is heavier on the page.	9.2%	9.2%	0.0%
Stroke contrastHorizontal stroke divided by vertical. 1.0 is even; below 0.5 means strong thick-thin modulation.	0.76	0.70	0.05
Average character widthMean lowercase advance. Higher takes more horizontal space.	49.5%	48.9%	0.6%

x-height: Lato measures 50.6%, Arimo measures 52.8%. Height of lowercase letters, as a share of the font size. Higher reads larger at the same point size.
x-height to cap ratio: Lato measures 0.71, Arimo measures 0.77. Proportion of lowercase to uppercase. Higher feels more modern and open.
Stroke contrast: Lato measures 0.76, Arimo measures 0.70. Horizontal stroke divided by vertical. 1.0 is even; below 0.5 means strong thick-thin modulation.