In-flight Wi-Fi has increased in availability and quality in 2018, according to flight booking website Routehappy's annual in-flight Wi-Fi rankings.

Measuring Wi-Fi quality by available seat miles (ASM)—the number of seats multiplied by the number of miles flown—the report found that a total of 82 airlines now offer Wi-Fi, up 17 percent from 2017. And 43 percent of all ASMs worldwide now offer Wi-Fi, up 10 percent from 2017.

How fast is in-flight Wi-Fi? Only 16 percent of ASMs have what Routehappy designates as Best Wi-Fi or a connection capable of full media streaming, while 57 percent are equipped with Better Wi-Fi, meaning a connection capable of full web browsing but only limited media streaming.

If you want to guarantee that you'll have in-flight Wi-Fi, choose your airline wisely. Southwest, Virgin Atlantic, and Icelandair all offer Wi-Fi on 100 percent of flights, and 13 airlines—Delta, United, Virgin Atlantic, Air Europa, Emirates, Etihad, Eurowings, EVA Air, Iberia, Kuwait, Lufthansa, SAS, and Scoot—offer Wi-Fi on 100 percent of long-haul flights.

See how top airlines stack up in this graph:

Routehappy

[h/t Travel + Leisure]