WRNJ (1510 AM) is a commercial radio station in Hackettstown, New Jersey. It broadcasts an adult contemporary radio format and is owned locally by WRNJ Radio, Inc.

By day, WRNJ is powered at 2,000 watts. But because AM 1510 is a clear channel frequency reserved for Class A WLAC in Nashville, WRNJ must reduce power at night to 230 watts.

WRNJ began operation on AM 1000 on August 26, 1976. It was a daytime only station with no pre-sunrise or post-sunset authorization, except for local emergencies. WRNJ employed a full-service adult contemporary format with an emphasis on local and national news. WRNJ also had local talk shows featuring local leaders and volunteers. Larry Tighe originally owned the radio station.

For many years WRNJ was not profitable. By the early 1980s, there were rumors that the station may even go dark. At that point, Norman Worth, who was the only person selling a substantial amount of advertising, became sales manager. Months later the station began turning a profit. By the late 1980s, Worth became part owner of the station and took over as General Manager and eventually as Chief Operating Officer.

In 1992, Worth was awarded an FM license on 107.1 FM. That station became WRNJ-FM and aired a country music format. In 1996, WRNJ AM was granted a 24-hour license on 1510 kHz. AM 1000 to Westinghouse Broadcasting, freeing the company to boost the power of its New York City AM station WINS 1010. That year, WRNJ moved from AM 1000 to 1510. It kept the Adult Contemporary format initially. It also began operating from 5 a.m. to 10 p.m. daily.

In 1997, it was determined that the station's towers could not transmit the correct nighttime patterns. WRNJ reverted to daytime-only operation. The current music also was phased out and the station evolved to more of an oldies format. By 1998, it was known as "Oldies 1510 WRNJ". The station still continued to be profitable despite the daytime-only operation. At the same time, management sold the FM station at 107.1 MHz to Big City Radio. WRNJ-FM became WWYY and joined the Country Music Y 107 triplecast making that station a quad cast. It switched to a Spanish-language tropical music format in 2002. In 2003 those stations were sold to Nassau and Nassau broke up the quadcast. Today the station is licensed to Belvidere, but broadcasts from Stroudsburg. It simulcasts country station WCTO in Easton, Pennsylvania.

In 1999, Oldies 1510 WRNJ began 24-hour-a-day operations. It aired satellite-delivered oldies programming for much of the day. But WRNJ retained its morning show, specialty shows, local news, and local talk shows. In 2004, WRNJ dropped satellite programming. It aired a full-service format that plays adult contemporary but talk shows were also featured.

The sale of WRNJ-FM in 1998 excluded the FM translators on 92.7 in Washington Township and on 104.7 in Hackettstown. WRNJ's owners retained these to rebroadcast the AM signal. In 2009, the oldies format evolved to a classic hits format focusing on 1970s and '80s hits. In 2014, the station returned to a mix of adult contemporary and classic hits, with the slogan "Today's Hits and Yesterday's Favorites." The playlist was mostly from the '80s, '90s, and 2000s, but with a few titles from the '60s and '70s.

In addition to its main signal on 1510 AM, WRNJ broadcasts on the following FM translators:

Call sign	Frequency	City of license	FID	ERP (W)	Class	Transmitter coordinates	FCC info
W224AS	92.7 FM	Washington, New Jersey	54693	150	D	40°48′28″N 74°57′32″W / 40.80778°N 74.95889°W / 40.80778; -74.95889 (W224AS)	LMS
W284AQ	104.7 FM	Hackettstown, New Jersey	54698	250	D	40°51′19″N 74°46′42″W / 40.85528°N 74.77833°W / 40.85528; -74.77833 (W284AQ)	LMS
W289CR	105.7 FM	Glen Gardner, New Jersey	202425	218	D	40°41′30.5″N 74°55′29.6″W / 40.691806°N 74.924889°W / 40.691806; -74.924889 (W289CR)	LMS

• Bernie Wagenblast

• WRNJ Radio homepage
• Facility details for Facility ID 76913 (WRNJ) in the FCC Licensing and Management System
• WRNJ in Nielsen Audio's AM station database