Radio KKRZ-FM (Z100 Portland's #1Hit Music Station)

KKRZ is a commercial broadcast radio station in Portland, Oregon, also known as Z-100, broadcasts Top 40 (CHR) music.

What is now KKRZ first signed on in 1947 as KGW-FM. The call letters changed to KQFM in 1955 and broadcasted a beautiful music format (as "Q-Music") and then in 1978 switched to a pop AOR format under the name "Q-100". The format was changed to oldies on March 16th, 1981 as "Solid Gold FM-100". The station changed to the KKRZ call letters and changed to what is considered a Hot AC format as "The Rose" (hence the KKRZ call letters) in 1983. KKRZ began its current heritage Top 40 format on March 16th, 1984, widely mirroring sister station WHTZ/New York City (down to the name "Z100").

In 1986, the station adopted a more rhythmic leaning format due to the lack of an existing Urban Contemporary FM. That move would pay off and make KKRZ a dominant success in the ratings in its first 15 years. That was until 1999, when it picked up competition from Rhythmic Top 40 rival KXJM who took advantage of the market's rhythmic void and filled it. This competition between the two would last for nine years, as KXJM (whose playlist favored Hip-Hop/R&B and some Dance product) would overtake KKRZ (who shift back to a more mainstream direction) in the Portland Arbitrons. After KXJM, who saw their ratings decline by 2007, announced their format flip to Sports Talk as KXTG in May 2008, KKRZ started to lean towards Rhythmic crossovers again, but would end up facing new competition from CBS Radio outlet KVMX, who ironically, dropped their Rhythmic Adult Contemporary and picked up KXJM's Rhythmic format and intellectual property, including the KXJM calls and "Jammin'" slogan, from Rose City Radio Corporation, the owners of KXTG. KKRZ would later move towards the center again and became a more balanced Top 40/CHR, which helped regain their foothold in the ratings again as well.

In April 2009 Clear Channel took over ownership of KXJM, thus making KKRZ and KXJM sister stations. Both stations retained their respective formats. However, in March 2010, KXJM was "relaunched" as "WiLD 107.5" but kept its Rhythmic Top 40 format intact. Despite the fact that both KKRZ and KXJM are under the same ownership, being programmed by the same program director and sharing some of the same music, KKRZ continues to focus on Mainstream Pop/Rock hits. In addition, both stations continue to place among the top 10 in the Portland Arbitrons.