A perfect all-kill (; abbreviated as PAK) occurs when a song simultaneously places at number one on the real-time, daily, and weekly components of iChart, which tracks South Korean music streaming services. iChart is run by Instiz Corporation, the South Korean web entertainment publisher that also operates the web forum.
The term "perfect all-kill" was first used when the song "Nagging" by IU featuring Seulong ranked at number one on all Korean music charts in June 2010. Although Instiz iChart was launched in March 2010, it does not list 2010 records. The artist that holds the record for the highest number of songs to achieve a PAK is IU with 22 songs. The song with the most hourly PAKs is "Golden" by Ejae, Audrey Nuna, and Rei Ami as the group Huntrix with 1,484 PAKs. "Good Goodbye" by Hwasa holds the record for a solo act with 750 PAKs.
The Instiz iChart aggregates the real-time, daily, and weekly rankings of major music streaming services in South Korea, including Melon, Genie, Bugs!, Vibe, Flo, and YouTube Music, producing its own real-time and weekly rankings based on points given to songs. The users can also visit the source agencies' websites directly to compare rankings. The records may be accessed by the public for three months.
Before 2015, the iChart aggregated scores from ten music service providers: Melon, Mnet, Bugs!, Olleh, Soribada, Genie, Naver, Daum, Cyworld, and Monkey3. In February 2017, major domestic music distributors changed their streaming calculation to real-time graphics only between 12pm and 6pm. This meant that anything that was released outside of this time would not count towards the chart until 1pm the following day. In May 2017, Olleh and Monkey3 were excluded from the Instiz iChart ranking calculation and Naver Music's score doubled. In February 2019, Flo was added to iChart. In October 2019, Mnet discontinued its service and merged with Genie, and was later removed from the chart. Naver Music has also been removed and replaced with Naver VIBE.
In May 2020, Melon made some changes to its real-time ranking calculation. The chart changed from rankings based on hourly usage per song to a chart calculated based on the number of unique listeners. Streams and downloads from the last 24 hours were calculated instead of the last hour.
The iChart gathers the data and attributes points to each song. The Instiz iChart attributes bonus points for more popular and widely used platforms than others. It applies a multiplier to the accumulated points that a song gets from certain charts. This multiplier only applies on daily charts. The following table shows the maximum points for every chart.
Other "all-kill" categories on the Instiz iChart include Real-time All-Kill (RAK) and Certified All-Kill (CAK). RAK is achieved when a song becomes number one on all iChart real-time charts while CAK is achieved when a song becomes number one on all iChart real-time and daily charts. For a song to achieve a PAK, it needs to become number one on iChart weekly chart as well.
The following table lists the top ten songs with the highest number of perfect all-kills (in hours), from 2010 to present.
The following table lists the top artists with the highest number of songs that have achieved a perfect all-kill from 2010 to present.