Next.js fix guide
Fix Duplicate IDs on Next.js
IDs must be unique in the DOM.
This page ties the generic issue to how it usually shows up in Next.js markup and tooling, then walks you through a fix and verification loop.
Verify on a live URL
Scan, fix, deploy, then rescan the same address to compare reports.
Main issue guide: Duplicate IDs →
At a glance
Instructional
Confusing tab order
DOM order matches layout
Duplicate IDs and broken ARIA relationships confuse assistive tech when it resolves references.
Where this comes from on Next.js
App Router layouts, client boundaries, and `next/*` components—verify the built HTML, not only source.
What this issue means
Fix
Rename duplicates; generate stable unique ids for lists rendered in loops.
How to fix on Next.js
In Next.js, verify both server and client components: hydration can change roles/names. Use `next/image` with meaningful `alt`, and ensure dynamic imports do not drop focus management.
How to fix
Ensure ids are unique per document; generate stable unique ids in lists.
Fix templates so duplicated components do not reuse hard-coded ids.
Common mistakes on Next.js
- Assuming dev overlay errors match production a11y tree.
- Ignoring dynamic imports that shift structure.
How to verify the fix
- Test the production build (focus and hydration differ from dev).
- Verify both mobile and desktop layouts if they diverge.
- Rerun the scan; compare rule counts on the same path.
Related: 4.1.1 Parsing (historically); best practice for robustness.
Same issue on other platforms
Related issues
Guides
Next steps
- Run a scan on staging or production.
- Re-read the main issue page for context and WCAG notes.
- React and Next.js accessibility hub for more platform resources.
TestAccessibility · Next.js fix · localhost:3001