IB grade to percent:
7=96%
6=90%
5=86%
4=76%
3=70%
2=60%
1=50%

25 point IB rubric to percent:
25=100
24=98
23=96
22=94
21=93
20=92
19=91
18=90
17=89
16=88
15=86
14=83
13=79
12=76
11=74
10=72
9=70
8=65
7=60
6=58
5=55
4=52
3=50
2=45
1=40

20 point IB rubric to percent:
20=100
19=99
18=98
17=97
16=96
15=94
14=92
13=90
12=89
11=88
10=86
9=80
8=70
7=68
6=65
5=63
4=60
3=50
2=45
1=40