Here is a scale used to convert grades if your home University doesn’t use ECTS grading system.

Poland ECTS  Canada China Indonesia Sri Lanka Vietnam
2 – failed F, FX 0 below 60 1 34 – 0 0,0
3 – sufficient E 1.0 – 1.3 60-69 2 35 – 44 1,0 – 1,5
3,5 – satisfactory D 2.3 – 1.7 70-74 2,5 59 – 45 2,0 – 2,5
4 – good C 3.3 – 2.7 75- 84 3 69 – 60 3,0 – 3,5
4,5 – very good B 3.7 85 – 89 3,5 84 – 70 4,0 – 3,5
5 – excellent A 4.0 90-100 4 85 – 100 4,0