Country wage rankings are almost always built from mean earnings converted at one rate or another, which makes them sensitive to three things that have nothing to do with living standards: the currency, the skew of the distribution, and whether the figure is gross or net. A ranking that changes order when you switch from exchange rate to purchasing power, or from mean to median, was never measuring what it claimed.
What these rankings actually rank
Most are average annual earnings for full-time employees, converted to a common currency. Every part of that carries a choice: which employees, which conversion, mean or median, gross or net.
Change any one and the order changes. That is not a flaw in one ranking; it is what the underlying data supports.
Why the mean is the wrong statistic here
Countries differ enormously in how unequal their earnings are. A country with a long upper tail has a mean well above its median, so it ranks higher on average earnings than on what a typical person earns. Comparing means across countries with different distributions compares different points of each distribution.
Where median figures are published, they are the ones to use, and the ranking they produce is materially different.
Gross, net, and the thing in between
A ranking on gross pay flatters countries that fund public services through employee taxation. A ranking on net flatters those that fund them through employer contributions instead. Neither is wrong; they are answering different questions, and almost no published ranking says which one it used.
What a country-level figure cannot tell you
What your occupation pays there. The variation between occupations within any country dwarfs the variation between country averages, so a high-ranking country can pay your particular work poorly and a low-ranking one can pay it well.
That is the more useful question and it is answerable only where occupation-level data exists, which is a much shorter list.
Where the rankings are genuinely useful
As a rough sort. The broad tiers are stable across methods even when the order inside them is not, so they tell you which countries are in a comparable band to your own. That is a real use and it is a good deal less than what they are usually cited for.
Common questions
Why do country wage rankings disagree with each other?
Because each involves choices about which employees, which currency conversion, mean or median, and gross or net. Change any one and the order changes.
Should I use the mean or the median?
The median where it is published. Countries differ in how unequal earnings are, so comparing means compares different points of each distribution.
Does a high-ranking country pay my job well?
Not necessarily. Variation between occupations within a country dwarfs the variation between country averages, so a high-ranking country can pay your work poorly.
Gross or net rankings?
Gross flatters countries funding services through employee taxation; net flatters those using employer contributions. Almost no published ranking says which it used.
Are these rankings useful at all?
As a rough sort into broad tiers, which are stable across methods. That is considerably less than what they are usually cited for.