NIB or nib may refer to:
- N.I.B., a song by Black Sabbath
- Neodymium magnet or NIB, a powerful magnet made from neodymium, iron, and boron
- Nib, a type of variable in PBASIC which stores Nibble values in the range of 0 to 15
- Nib, partially processed cocoa bean
- NIB, is a term used on an eBay post to state that the item listed is "New In Box"
- Twizzlers Nibs, a bite-size cherry-flavored licorice candy
- Nibs, a term used in the card game cribbage
- Nibs, one of the lost boys in the book Peter Pan
- Nib (pen), a part of a quill, dip pen or fountain pen
- Nib, the generic name assigned to .nib and .xib files, the default file format of the computer program, Interface Builder.
In companies and organizations:
- National Institute of Broadcasting, a broadcast training school in Toronto, Ontario, Canada
- National Institute of Building Sciences, a non-profit private organization
- National Irish Bank, a major bank in Ireland
- National Intercollegiate Band, an American band sponsored by Kappa Kappa Psi and Tau Beta Sigma, honorary band fraternity and sorority
- Nordic Investment Bank, the joint international financial institution of Denmark, Finland, Iceland, Norway, and Sweden
- Novin Investment Bank, one of the first investment banks in Iran
- nib health funds, an Australian private health insurer
- Amtrak station code NIB for New Iberia (Amtrak station), in Louisiana United States
- National Internet Backbone, The internet backbone of BSNL, through which it provides High-Speed Broadband all over India