Not in the BtN database, but you might like to have the Afrikaans version in your own one.
Looks like
Frederik. Sounds like ... not the Dutch, actually. The first syllable is stressed, and has a long E sound followed and diphthongised by a neutral vowel: like 'ear' if you don't sound the R. The unstressed syllables are neutral-vowel-tending-towards-uh.
Nicknames include
Freek (same long E), Frik and Derik (which often sounds like the English
Derek) as well as the more international
Fritz.