A high school diploma is a certificate awarded for the completion of high school. While there is no central database for verifying high school diplomas, it is possible to find out if someone has received a high school diploma by contacting individual schools. Most schools will not release information without written authorization, so before you can verify a diploma, you need to obtain written authorization from the individual.
Ask the person for the name of the high school he received the diploma from and his graduation date.
Prepare a form for the person to sign that authorizes you to verify the person received a diploma from the school. Have the person sign and date the form.
Verify the high school's accreditation from the NCES. You can use the NCES's online search tool (see Resources) to find contact information for all accredited public and private high schools in the United States. If the high school appears in the NCES's list, the high-school is accredited.
Call the high school using the contact information listed on the NCES website. Tell the operator that you need to verify a high school diploma. The operator will ask you to fax in the written authorization. Fax in the written authorization and call back to verify the high school diploma.