For a webpage to be considered a valid Accelerated Mobile Page (AMP), it must adhere to a strict set of technical specifications. The most fundamental of these is the starting `<html>` tag itself. A missing `amp` or `⚡` attribute in the `<html>` tag is a critical validation error that instantly disqualifies the page from being treated as AMP by search engines and other platforms.
Think of this tag as the official seal on a legal document. Without that seal, the document is not valid, no matter how well-written the content inside may be. This simple attribute is the first signal that tells a crawler, “This is an AMP document; process it according to AMP rules.” For a broader look at AMP, see our main guide on AMP.
Why the `amp` Attribute is Non-Negotiable
The AMP specification is very clear: every AMP document must start with `<html ⚡>` or `<html amp>`. As detailed in the official AMP documentation, this is a mandatory requirement.
- AMP Validation: This is the first check that any AMP validator performs. If the attribute is missing, the page fails immediately, and no other checks are performed.
- AMP Cache Eligibility: Only valid AMP pages are eligible to be served from the super-fast Google AMP Cache. A missing attribute means your page will not be cached.
A Step-by-Step Guide to Fixing the Missing Tag
This is one of the simplest yet most critical fixes for any AMP page. For more on the relationship between AMP and non-AMP pages, see our guide on AMP canonicalization.
Example: Adding the `amp` Attribute
<!-- Before: Missing amp attribute -->
<!doctype html>
<html lang="en">
<!-- After: amp attribute added -->
<!doctype html>
<html ⚡ lang="en">For more on this topic, see our guide on on-page SEO.
Frequently Asked Questions
What is the purpose of the ⚡ symbol?
The lightning bolt symbol (⚡) or the word `amp` in the `<html>` tag is the official identifier that tells browsers, crawlers, and other systems that the document is an AMP page. It’s the first thing an AMP validator looks for.
Can I use both `amp` and `⚡` in the tag?
No, you should use one or the other, not both. Both `<html ⚡>` and `<html amp>` are valid, but the lightning bolt is more common and visually distinctive.
How can I check if my AMP pages have the correct tag?
The most effective way is to use Google’s official AMP Test tool. It will immediately tell you if your page is valid AMP, and a missing `<html>` tag attribute is one of the first and most basic errors it will report.
Is your AMP missing its spark? Start your Creeper audit today to find and fix all your AMP validation errors.