Hi, as a Nigerian student, will my total GPA be calculated with my high school transcripts alone or my WAEC result will be included in the calculations .
Your GPA, whether it's your unweighted GPA or your weighted GPA is solely based on your high school grades on your official transcripts. Nothing more and nothing less. You WAEC test results and scores are not factored into your GPA.
Similarly, if you have an SAT or ACT score, these standardized test scores are not added or mixed into your GPA in the USA. They are separate optional requirements that are evaluated on their own in context with your academic narrative which includes the courses you have completed, your grades and their category as either standard courses, honors course, APs, IBs, or dual enrollment college classes. External college courses are not factored into your GPA unless your HS counselor/school authorize that your college work meets your graduation requirements and can be counted.
Since the WAEC is not a requirement to apply to American colleges, it is up to you to share that information in the add'l information section of your "common app". I would do so especially if it an exceptionally high score.
Good luck.
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