How to fix non iso date on WooCommerce

Steps for WooCommerce

1. Install and activate the 'Yoast SEO' or 'Rank Math SEO' plugin if not already present — both output ISO-8601 dates automatically for most schema types.
2. If you have custom or theme-generated JSON-LD, go to Appearance → Theme File Editor (or use a child theme) and locate the file outputting structured data — often 'functions.php', 'single-product.php', or a dedicated schema file.
3. Find any PHP date output and replace informal formats with: date('Y-m-d\TH:i:s\Z', strtotime($date_string)) or use WordPress's built-in: get_the_date('Y-m-d\TH:i:s\Z').
4. For Yoast SEO: Settings are mostly automatic; verify under SEO → Search Appearance → Content Types that the correct post/product types are enabled for schema output.
5. For Rank Math: Go to Rank Math → Titles & Meta → Posts/Products and confirm Schema type is set; Rank Math handles ISO formatting natively.
6. Test any updated product or post URL in Google's Rich Results Test to confirm dates pass without warnings.

{
  "@context": "https://schema.org",
  "@type": "WebPage",
  "name": "My Product Page",
  "datePublished": "2019-09-23",
  "dateModified": "2024-03-15T09:30:00Z"
}

What is non iso date?

Structured data (the behind-the-scenes code that tells Google what your page is about) includes date fields like `datePublished` and `dateModified`. These dates must be written in a specific international format called ISO-8601 — which looks like `YYYY-MM-DD` (for example, `2019-09-23`) or with a full timestamp like `2019-09-23T00:00:00Z`. When dates are written in a casual format like "09/23/2019 00:00:00" or "September 23, 2019", search engines cannot reliably parse them and may ignore them entirely. Think of it like filling out an official form: the field has a required format, and anything else gets rejected.

Google uses `datePublished` and `dateModified` to understand content freshness — a key signal for ranking pages in news, article, product, and general search results. If Google can't parse your date, it may estimate the wrong publish date or show no date at all in search results, making your listings look outdated or untrustworthy compared to competitors whose dates are formatted correctly. For Answer Engine Optimization (AEO), freshness signals help your content surface in AI-generated answers and featured snippets, where recency is often a deciding factor. A malformed date can also cause your structured data to fail Google's Rich Results Test, disqualifying your pages from rich result enhancements like breadcrumb trails, review stars, and FAQ dropdowns — all of which directly impact click-through rates and organic traffic.

See the complete Non iso date guide for every platform and the full background.