Q: What is the Data Cache in Next.js and how do you opt out of it?

The **Data Cache** stores fetch (and cached function) results on the **server across requests and deployments** to avoid refetching. Opt out per fetch with cache: 'no-store' , per segment with export const dynamic = 'force-dynamic' or revalidate = 0 — so data is always fresh. <rect class='d-box-accent' x='2

Question 1

What is the Data Cache in Next.js and how do you opt out of it?

Accepted Answer

The **Data Cache** stores fetch (and cached function) results on the **server across requests and deployments** to avoid refetching. Opt out per fetch with cache: 'no-store', per segment with export const dynamic = 'force-dynamic' or revalidate = 0 — so data is always fresh.

Question 2

What are the caching layers in Next.js (Request Memoization, Data Cache, Full Route Cache, Router Cache)?

Accepted Answer

**Target Audience:** Frontend engineers preparing for Next.js interviews — assumes basic React and App Router familiarity.
**Difficulty:** Hard

> **How to read this doc:** Each idea is explained in plain language first, then tagged with `📌 Interview term:`. Every behaviour claim was checked against the Next.js docs shipped with the package (written on 16.3.4, re-reviewed against 16.4.2) and, in the **Verified** section, against real output from a build or a running server; each Verified block

NEXT.JSDECODED.

Medium

What is the Data Cache in Next.js and how do you opt out of it?

Hard

What are the caching layers in Next.js (Request Memoization, Data Cache, Full Route Cache, Router Cache)?