Faking a high school diploma is punishable by law. Nonetheless, people will forge this document in order to qualify for a job or to be admitted to an institution of higher learning. If you doubt the authenticity of a high school diploma, request the candidate to provide official transcripts to verify his attendance, but be beware that he may forge these too.
Look for spelling errors on the diploma. Chances are, the person who has forged the document will be very careful not to misspell any words or make any typographical errors, but make the review anyway, as this kind of mistake would easily identify a fake diploma.
Feel the texture of the paper of the diploma. Place the diploma between your thumb and index finger to feel how heavy the paper is, as legitimate diplomas are printed on heavyweight paper. The paper should also feel slightly glossy, which is necessary for the document to be preserved over time.
Examine the diploma carefully for any toner or printer ink marks or blotches. Since authentic diplomas are not printed on commercial printers (they are stamped and pressed by a professional company), they will not have ink marks.
Examine the diploma carefully to see if the text is perfectly centered and aligned. Forged diplomas are normally made from commercial printers, which are more likely to distort or shift paper while pulling it through, as indicated by misaligned text.
Check whether the claimed high school exists, as the person may have created a fictitious institution. If the school is legitimate and nearby, visit the school to examine archived diplomas and confirm that the diploma conforms to the diplomas issued by the school for the year in which it has allegedly been issued.