Bike frame measurements
Each manufacturer sets its' own guidelines for frame sizing based on their frame geometry.  The only true way to judge what size frame you need is to ride the bike and see if it is comfortable. Don't buy if you can't ride it. Since frames are sized by more than one means of measurement there is no true standard. Some makers use small, med, large  others are numerically odd numbers and others are numerically even numbers. You might fit on one type of frame and the same size from a different company could be too large or too small. If you want to complicate things add in different wheel sizes 26"vs 27.5 vs 29er and it gets even more confusing.