If it's too long people might use In English: Gabe
For the opposite sex use: In Portuguese and in Romanian: Gabriela (F) In Italian and in Hungarian: Gabriella (F) In French: Gabrielle (F) In English, French, German, Spanish, Portuguese, Romanian and in the bible: Gabriel (M)
See also In Hungarian: Gabi (M) In English: Gabby (B)
Extra information: Alternative meanings (Italian) Strength of God