Web Novel

Re:Zero kara Hajimeru Isekai Seikatsu originally began as a web novel on Shousetsuka ni Narou, and its first chapter was released on April 20, 2012. While the author originally posted chapters there normally, the series was adapted as a Light Novel. He later used the Web Novel as a draft for the upcoming novels that were to be released until each of them caught up to each other. As the Web Novel is a draft, everything up to the latest Light Novel release in the Web Novel should be considered non-canon.

Arc 1: The Chaotic First Day
The Chaotic First Day (怒涛の一日目, Ōto no Ichinichi-hen) is the first arc of the Web Novel. It began on April 20, 2012, and it was finished on May 8, 2012. Arc 1 consists of a prologue, 22 chapters, and 1 interlude.

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

Arc 2: The Tumultuous Week
The Tumultuous Week (激動の一週間, Gekidō no Isshūkan) is the second arc of the Web Novel. It began on May 9, 2012, and it was finished on July 8, 2012. Arc 2 consists of 49 chapters and 1 interlude.

The second arc is about Subaru's 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 mysteriously murdered. Willing to discover the killer, Subaru will do everything possible to gain the trust of everyone at the mansion and achieve the desired outcome; saving himself and everyone he cares about.

Arc 3: The Return to the Capital City
The Return to the Capital City (再来の王都, Sairai no Ōto) is the third arc of the Web Novel. It began on July 16, 2012, and it was finished on April 19, 2013. Arc 3 consists of 84 chapters, 3 interludes, 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 brutally murdered by the mysterious Witch Cult. While repeatedly dying and returning, Subaru encounters new opponents and obstacles, finds clues, and discovers that in order to push through this seemingly unending nightmare, he'll have to ask for help.

Arc 4: The Everlasting Contract
The Everlasting Contract (永遠の契約, Eien no Keiyaku) is the fourth arc of the Web Novel. It began on April 20, 2013, and it was finished on August 3, 2014. Arc 4 consists of 130 chapters, 4 interludes, and 3 extra chapters.

The fourth arc is about Subaru and Emilia arriving at the Sanctuary, where they encounter Roswaal, Ram and the missing villagers of Arlam Village held hostage by a mysterious and aggressive boy. Roswaal instructs the two of them to carry out the Trials of the Sanctuary, in order to liberate the Sanctuary and save the demi-humans trapped in it by a mysterious barrier. However, the journey starts to get complicated, as using his Return by Death to gain insight on how to bypass each obstacle proves ineffective.

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. It began on September 17, 2014, and it was finished on August 13, 2015. Arc 5 consists of 81 chapters, 3 interludes, and 3 extra chapters.

The fifth arc is about Anastasia inviting the Emilia, Crusch, Priscilla, and Felt Camps to attend a gathering in the Watergate City of Priestella. Soon after their arrival at the Watergate City, the Witch Cult appears, taking control of the city and forcing Subaru to unite all camps in order to defeat the evil Cultists and liberate the city.

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. It began on August 15, 2015, and it was finished on November 4, 2020. Arc 6 consists of 90 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 battle in Priestella. Once they finally arrive after much trouble, the tower's Stars-Keeper, Shaula, tells them that in order to gain knowledge, they must complete the Pleiades Watchtower's three Trials. However, in the process of doing so, old enemies looking to settle a score reappear alongside new faces who should not be there.

Arc 7: The Land of the Wolves
The Land of the Wolves (狼の国, Ōkami no Kuni) is the seventh arc of the Web Novel. It began on January 21, 2021, and it is the current ongoing story arc. Arc 7 currently consists of 114 chapters and 2 extra chapters.

The seventh arc is about Subaru who, alongside Louis and Rem finds himself in a mysterious jungle, which soon turns out to be the Buddheim Jungle located in the Kingom's neighbouring nation–the Sacred Empire of Vollachia. Immediately after waking up, however, disaster strikes–Rem, who has just regained her consciousness after nearly two years of being in a vegetative-like state, does not recognise Subaru and considers him her enemy. Furthermore, Subaru soon entangles himself in a deadly conflict, unintentionally siding himself, Rem and Louis with the former 77th Emperor of the Vollachia Empire–Vincent Abellux, who asks Subaru to assist him in his campaign to regain the Imperial throne. However, as the Emperor is a wanted man, Subaru constantly needs to watch his back for assassins and the Imperial Army who want both Vincent's and Subaru's heads.

Re:Zero IF
The Re:Zero IF chapters are web novel chapters posted each April Fools'. To celebrate Natsuki Subaru's birthday, the author writes a chapter or chapters which deviate 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 resembles 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 nine, with Arc 2 and an unknown Arc being added later.
 * The Web Novel does not feature any illustrations except for the End of Sloth chapter in Arc 3 (chapter 80).
 * Arc 6 is the Arc that was being written for the longest time. As opposed to every other Arc beforehand, Arc 6 took Tappei roughly 5 years to complete.
 * In a Re:Zero Talkshow held back in 2018, Tappei Nagatsuki expressed his desire to name the final Re:Zero chapter Re：ゼロから始めた異世界生活 (Re:Zero − Having Started Life in Another World).