What a 3.7 on a 4.5 scale looks like on a 4.0 scale. Institutions differ, so treat it as a guide.
A linear conversion placing 60% at 0.0 and the maximum at 100%. Schools and credential evaluators use their own formulas, so prefer any conversion printed on your transcript.
Korean universities commonly use a 4.5 maximum while the 4.0 scale is standard elsewhere. No law fixes the conversion: schools, credential evaluators such as WES, and employers each define their own, so the same 3.7 becomes 3.29 in one place and 3.3 in another.
Most forms ask for the original GPA and its maximum (for example 3.7 / 4.5). Writing your own converted figure can conflict with the transcript. When an evaluator requires a conversion, follow that organisation's formula.
If your transcript prints a percentage, that value wins. The percentage here assumes 60% is 0.0 and the maximum is 100%.
No. The conversion runs in your browser.
It converts a single value. For a per-course average, use the figure on your transcript.
It depends on the school, which is exactly why you should check the maximum first.