Universal Men's Shoe Size Chart
I really like this mens shoe size chart as it clearly shows why traditional charts do not work – the reason lies in an uneven breakup of what constitutes a size. Therefore there is not an even one for one shift when examining sizes between systems. Frustrating, yes. But that's what we get with so many systems.
If you're looking to buy shoes in another country or in a system not your own, make sure the business has a good return system, that you have a plan B if the shoe doesn't fit, and if possible find a sample shoe from that sizing system to try on.
Best of luck finding that perfect fit.