Short answer: In the original Stranger Things timeline, Will Byers is in the Upside Down for about a week, though the experience feels much longer to him and to those watching, and the narrative implies a time gap of roughly several days up to a week between his disappearance and his rescue. Context and details:
- The on-screen pacing places his disappearance on November 6, 1983, with his rescue occurring days later. The events in season 1 suggest a time span of a week or so from abduction to return, even though the fear and tension make it feel longer to the characters [web results indicate roughly a week].
- In-universe notes and later materials tie Will’s time in the Upside Down to a relatively short window, though the trauma and illnesses he endures (including the slug and other effects) linger well after his return [web results indicate lasting impact].
- Season 5 material released in 2025 reinforces that Will’s earlier stay is counted in days/weeks, not months, though new scenes extend the mystery and provide more precise framing of the timeline than Season 1 alone [web results discuss early minutes and reveal new context].
Notes for nuance:
- Some fan discussions and articles debate exact counts (6–7 days vs. roughly a week), but the consensus in official and major media reporting aligns with a timeframe of about a week, with the Upside Down “time” effectively paused or slowed relative to Hawkins’ clock.
- The Upside Down’s time anomaly is a recurring element in the lore, often summarized as time not progressing in the UD in the way it does in the real world, which supports the sense that Will’s stay was shorter in real-world terms than his experience would suggest.
If you’d like, I can pull more precise quotes from the latest Season 5 material or compile a quick timeline with dates as shown in the show’s narration.
