Web Novel

Re:Zero kara Hajimeru Isekai Seikatsu originally began as a web novel on Shousetsuka ni Narou, with the first chapter being released on April 20, 2012. Since then, the author has used it as a draft for the upcoming light novels and releases chapters occasionally whenever he has time to continue it. As the web novel is a draft, everything up to the latest light novel release in the web novel is now non canon.

Arc 1: Chaotic First Day
Chaotic First Day (怒涛の一日目) is the first arc of the web novel. The first chapter was released on April 20, 2012, and finished on the May 8, 2012, with the arc consisting of a prologue, 22 chapters, and an interval.

The first arc is about Natsuki Subaru's arrival in the new, mysterious world he has been summoned to. There, in the Kingdom of Lugnica, he decided to help a silver-haired, amethyst-eyes girl with recovering her stolen insignia. However, he ends up being murdered by someone, but Returns from his death, and decided to use this ability to save that girl from her predestined death.

Arc 2: The Tumultuous Week
The Tumultuous Week (激動の一週間) is the second arc of the web novel. The first chapter was released on May 9, 2012, and finished on the July 8, 2012, with the arc consisting of 49 chapters and an interval.

This second arc is about Subaru accommodation in the Roswaal's Mansion, where he started working as a butler with Ram and Rem, but nevertheless, in his first days of working, he was murdered mysteriously. Willing to discover the killer, Subaru will do everything possible to gain the trust of everyone at the mansion.

Arc 3: Return to the Capital
Return to the Capital (再来の王都) is the third arc of the web novel. The first chapter was released on July 16, 2012, and finished on the April 19, 2013, with the arc consisting of 84 chapters, 3 intervals, and 2 extra chapters.

The third arc is about Subaru, who after embarrassing Emilia in the Royal Capital, is left to be treated by Crusch Karsten. Soon after, Subaru and Rem return to the mansion, only to discover that everyone of the Emilia Camp was dead. While striving forward, Subaru finds clues, and is convinced that he cannot fight his enemies alone, thus seeks as much help as possible.

Arc 4: The Everlasting Contract
The Everlasting Contract (永遠の契約) is the fourth arc of the web novel. The first chapter was released on April 20, 2013, and finished on the August 3, 2014, with the arc consisting of 135 chapters, 4 intervals, and 3 extra chapters.

The fourth arc is about Subaru being broken by the loss of Rem. Later, he and Emilia arrive at the Sanctuary to bring back the villagers of the Irlam Village. However, a badly wounded Roswaal L Mathers instructs the two of them to carry out the Trials of the Sanctuary, with the examiner of the Trials being the Witch of Greed, to liberate the Demi-Humans from the barrier. However, the journey starts to get complicated.

Arc 5: The Stars That Engrave History
The Stars That Engrave History (歴史を刻む星々, Reikishi wo Kizamu Hoshiboshi) is the fifth arc of the web novel. The first chapter was released on September 17, 2014, and finished on the August 13, 2015, with the arc consisting of 81 chapters, 3 intervals, and 3 extra chapters.

Arc 6: The Corridor of Memories
The Corridor of Memories (記憶の回廊, Kioku no Kairou) is the sixth arc of the web novel. The first chapter was released on August 15, 2015 and the arc is currently ongoing. Currently, the arc consists of 79 chapters and 7 extra chapters.

The sixth arc is about Subaru who leads a team to the Pleiades Watchtower to gain knowledge regarding how to fix the problems caused during the duel in Priestella. Once they finally arrive after much trouble, Shaula tells them that to gain knowledge, is to complete the trials corresponding to the floor. However, in the process of doing so, enemies reappear.

Re:Zero IF
The Re:Zero IF chapters are web novel chapters posted each Aprils Fools. To celebrate Natsuki Subaru's birthday, the author writes a chapters which deviates from the original web novel. They are around four times longer than normal chapters and show what would've happened if Subaru did something contrary from what he actually did. Each of the chapters resemble one of the seven deadly sins.

Trivia

 * Currently, only one Web Novel chapter has been removed from the Web Novel, which is the Butterfly's Dream What IF Story.
 * According to the author, there will be eleven arcs, though he originally planned for ten.
 * The Web Novel does not feature any illustrations except for the End of Sloth chapter in arc 3 (chapter 80).