Target Corp. is jumping on the Christmas-in-July bandwagon.

The Minneapolis-based discount store chain said it will host its first-ever Back in Black Friday sale online only on Friday, offering an average markdown of 40 percent on more than 500 items in apparel, electronics, toys, housewares, movies, music and books.

Target joins rivals Toys R Us, Sears and Kmart as mass merchants make a grab for a share of consumers’ shrinking budgets by giving them reasons to shop for the holidays early.

The Friday after Thanksgiving, known as Black Friday, is considered the official start of the Christmas shopping season.

Toys R Us Inc. unveiled its first Christmas Savers Club last month and is holding its first-ever Cyber Monday sale in July. Cyber Monday is the retail industry’s much-hyped online shopping bonanza that takes place the Monday after Thanksgiving. The toy store chain is also running weeklong Christmas-in-July sales for the second year in a row this week.

Likewise, Sears Holdings Corp. has brought back its Christmas Club savings card and Christmas Lane shops this summer at Sears and Kmart (online and at selected stores) — concepts conceived last year as the retailer looked for ways to cope with consumers’ newfound frugality.