As defined on the Soompi website, “When an artist has the #1 song or album on all the legal music download sites, such as Melon, Dosirak and Soribada. An all-kill on a daily chart (on the day of a new release) is normal for most popular groups. Weekly and monthly chart all-kills are much more difficult.”

An even more difficult feat is to achieve a perfect all-kill, which is defined on the Onehallyu forums:

“Perfect All-Kill on Instiz means that a song achieves #1 everything: #1 on all realtime charts #1 on all daily charts #1 on Instiz Weekly Chart, which is updated hourly, by adding hourly points of the song into its weekly cumulative point”.