CLB could mean
- Columbus Blue Jackets, a National Hockey League (NHL) team, based in Columbus, Ohio
- "Church Lads' Brigade", a former name of the Church Lads' and Church Girls' Brigade
- Columbia Lighthouse for the Blind
- Configurable Logic Block (cf. FPGAs)
- In China, China Labour Bulletin
- In India, the Company Law Board
- In Malaysia, Chung Ling High School, Butterworth
- In the United States Marine Corps, Combat Logistics battalion
- Church of the Lutheran Brethren of America
- In sport, an abbreviation for teams based in Columbus, USA
- In parenting, a method to sleep train a baby, from The New Content Little Baby book
- Component Load Balancing (CLB)
- Citrus long-horned beetle