Greece vs Turkey Simulation

The balance of power has always been in Turkey's favour. It has 7 times the population and 3 times the economy. For this reason, Greek military doctrine has never been about "guaranteeing" a victory over Turkey, since that would be economically destructive. Rather, the goal is to have a large enough, modern enough, credible enough force that (a) would push Turkey to avoid war, and (b) would not give Turkey a guarantee of victory if a war broke out.

Greece has such a force. For the less knowledgeable Yahoo posters out there, Greece has a large navy and air force that are only moderately smaller than their Turkish opposites. The Turkish army is far larger than the Greek army, but that is a misleading fact - there isn't much land connecting Greece and Turkey, and also the Turks have always been pre-occupied by Kurdish issues, so the Turkish army's numerical advantage is not nearly as great as it first seems.

As for the Cyprus situation someone mentioned, that is hardly a telling example of what would happen in a war between Greece and Turkey. Greece's contribution to that war was about 1000 liaison soldiers serving with the Greek Cypriots. That's it. The war was fought mostly by Greek Cypriots against the Turkish military. Greece was kept out of it by US aircraft carriers, from an American policy to hand Turkey the advantage. Besides, the arms holdings of both Greece and Turkey are now eons ahead of what they were in 1974.

So to answer your question, the short answer is this:
-In a war lasting less than a month (by far the most likely scenario), Turkey would have a 50-70% chance of winning. Such a war would be fought almost entirely air force, navy, and special forces in the army. There would be very little, if any, general army combat.
-In a war lasting a few months to a year, Turkey would have a 70-90% chance of winning because of higher industrial and economic capacity. This is assuming it managed to knock out Greek air power within a couple of weeks, which is hardly a guarantee, given the air force comparisons (numbers and quality) and the Greek radar/missile coverage (which is probably the densest in the world).
1) Tradingeconomics
3) Worldbank
4) IMF
5) Statista
6) UN

Other main sources:

National statistic agencies, ex: ''United States Census Bureau'', ''Statistics Belgium'', ''Badan Pusat Statistik'', ''Direction générale Statistique (Belgium)'', 'Istituto Nazionale di Statistica; Istat (Italy)''', etc.