---
title: "Keeping SEO when changing the theme"
url: https://phatdev.net/en/docs/iga/seo-parity
lang: en
updated: 2026-10-20
alternate:
  vi: https://phatdev.net/docs/iga/seo-parity
markdown: https://phatdev.net/en/docs/iga/seo-parity.md
---

# Keeping SEO when changing the theme

Part of the doc set: [IGA (Infinity Gems)](https://phatdev.net/en/docs/iga.md)

> Comparing 216 URLs between the old site and the test site.

## How it was measured
- A fixed list of **216 URLs**: the home page, 57 categories and their page 2, 77 products, 25 posts, 20 pages, tags, news, cart, checkout, search, filter URLs, 404, robots and sitemap.
- For each URL we compare: status code and redirects, `<title>`, meta description, canonical, meta robots, Open Graph, Twitter, H1 and JSON-LD.

## Result (13 Oct 2026)
| Result | URLs |
|---|---|
| Identical character for character | 4 |
| Differs only in intentional or better items | 212 |
| Unexplained differences | 0 |

Example of an improvement: the old site printed 2 conflicting canonical tags on `/page/N/` pages, while the new one prints exactly 1 self-referencing canonical.

## Internal links
2,231 internal links were checked; every URL that returned 200 on the old site returns 200 on the new one at the same path.

## After go-live
Monitor Search Console for at least 2 weeks, and prefer a 301 redirect over a 404 whenever a URL changes.