The 100 has been taking viewers to a post-apocalyptic hellscape every year since 2014, and the action between the ever-dwindling number of survivors has had a number of viewers hooked. The show has never been the highest-rated show on television (or even on The CW), but fans don't need to worry that it will get the axe after the end of its current fifth season. The CW has already renewed The 100 for Season 6.
The renewal order comes after only two episodes of Season 5 have hit the airwaves, which may be a sign that The CW has faith in The 100 to hold on to its chunk of the audience. It was one of only a handful of CW shows that did not have its fate decided back in April, so many fans likely expected to have to wait a while into the season before learning its fate. The renewal means that fans can relax a bit for the next 11 episodes. Sure, the lives of all the characters are in question and there's no limitation to the fresh dangers that await the survivors on the ground, but at least we know some of them will survive to fight again at least one more season.
Given The 100's numbers so far in Season 5, there was certainly no guarantee that the show would score a renewal. In Live+Same day calculations, the average rating in the key 18-49 age demographic is a meager 0.35, and only 1.2 million viewers on average have tuned in. That said, the Live+Same day calculations for Season 5 are already up from the 0.34 rating and 0.955 million viewers on average from Season 4. If Season 5 can hold onto its audience in the rest of the episodes, it could turn out to be a bigger hit than its previous season. Deadline reports that The 100's higher ratings than fellow CW series iZombie are what probably scored The 100 the early renewal.
It's much too early to do much speculation over what Season 6 of The 100 could possibly deliver. Most of the survivors from the earlier seasons have been separated for the six years that passed between Seasons 4 and 5, with Clarke on the ground with the prison ship, Bellamy and his small crew in space, and Abby, Marcus, and the other survivors trapped down in the bunker. Season 4 killed off a bunch of characters, and Season 5 already saw the end of Jaha. The possibility of another culling was teased, and the prisoners are unlikely to show much mercy. Plenty of people may be killed off before the end of Season 5; we can only cross our fingers and hope that our favorites don't bite the radioactive dust before the season finale.