Google's December 2025 Core Update: What SEO Professionals Need to Know About AI Content

Last Updated: December 13, 2025 | 4 min read

Google announced its December 2025 core update on December 11, 2025. This is Google's third core update of 2025. Google said the December 2025 core update will be rolled out over the course of three weeks. Google continues to highlight the importance of great authoritative and high-quality content as well as identifying AI-generated content in 2025.

Here's what's actually happening and why it matters for your SEO strategy.

What Changed in the December 2025 Update

While Google’s wording is broad - a normal update to “helpful and reliable content in Search” - early observations from SEO tools and experts do show some clearer patterns.

The newest update appears to put focus on E-E-A-T across a broader scope of content categories not limited to health and finance. Just before they rolled this out, they updated their guidance to make it clear that ranking changes may be from lots of little algorithm updates throughout the year and not just major core updates. Meaning Google is continually assessing quality of content throughout the year, as opposed to only at specific times.

The AI Content Reality Check

Pure AI content sites with no human curation are suffering significant declines. Early evidence from data shows sites with 90 to 100 percent AI content that is unedited are experiencing declines between 40 and 60 percent in their traffic. Sites with a mix of AI content with real human content and heavy editing are holding steady to growing.

But it’s not the AI content tools Google is targeting, it is poor quality content. The sites affected have common traits such as thin content, a flood of low-utility posts, or dreary writing that doesn’t demonstrate real expertise.

Leading up to and after this quality update, sites that improved had in many cases demonstrated deep knowledge by grouping related topics into separate areas (about a 23% increase). Sites also had a site owner that shared personal or first-hand expertise and offered unique insight rather than generic responses.

Why This Matters for SEO Professionals

The December update highlights a major challenge SEO practitioners face—leveraging AI's advantages against Google's evolving detection capabilities—a challenge for agencies and in-house teams managing high volumes of content creation.

Consider the costs. Having 100 posts per month written entirely by humans costs close to $7,500. Content created entirely by AI comes in at under $200, but carries a high risk of penalty, with a potentially significant impact on your lead time. The hybrid approach of AI-assisted human writing and editing at $3,900 offers a reasonable balance of risk and output.

But it’s not just about minimizing cost. It’s about creating sustainable competitive advantage. Organizations that embrace AI to augment human capability will dominate those that rely on manual labor and therefore move slower, or those that rely on AI alone and therefore produce inconsistent results.

What AI Humanization Actually Solves

The best AI humanization software emphasizes the elements Google evaluates. They remove recognizable AI language characteristics by swapping individual words, alter sentence structure for a smoother flow, and preserve SEO components like keywords and references so the content goes undetected as machine-made.

The highest priority is “quality.” The humanizer tools are quite different from each other. Also the ability to keep the citations (broken citations are a killer for E-E-A-T), having many bypass options to bypass different checks, and having a paragraph mode that adjusts the content (but keeps the parts you verified) are important.

Early feedback according to SEO experts trying out this method looks promising. An e-commerce digital marketing agency who dropped 67% of their site visits in March 2024 implemented an AI-powered technique to re-humanize their content and successfully brought back 89% of their visitors within 3 months. They are currently outperforming their pre-decline levels by 23%.

The Practical Workflow

The process involves three key stages. Initially, harness the power of AI to rapidly generate structured content and perform preliminary research. Subsequently, inject a human touch to disrupt the AI's repetitive patterns while preserving the main message and SEO benefits. Finally, refine with expertise, unique visuals, and fact-checking for added credibility.

This hybrid approach delivers what Google actually wants: content that demonstrates real expertise and provides genuine value to users, created efficiently enough to compete in today's market.

What About Ethics?

Myth #3. Google is against AI content. Google has also clarified that they don’t care how content is created. What matters to them is that it serves users well. Google does allow for content created with the help of AI, as long as it demonstrates knowledge and provides reliable information for users.

Problems occur when content is produced by AI without supervision, which may be false or misleading, or when massive amounts of very poor materials are produced simply to take advantage of keywords. It is the responsibility of SEO professionals to check facts, add real knowledge, and make sure everything is accurate before publishing.

Looking Forward

We see Google's direction more clearly: enhanced recognition of AI-generated content, refined E-E-A-T factors, and an intensified focus on user experience. The December update underscores the perils of exclusive AI-generated content, but utilizing AI for content support is still a dependable and effective method.

Victory in 2026 and beyond hinges on integrating human expertise with artificial intelligence. Approaches that deliver genuine insights, using AI to swiftly generate content, then meticulously reviewed and refined by humans, will outperform traditional methods and mass-produced AI content.

Action Items

If you want to address the SEO issues caused by this update or sidestep them entirely, focus on these three key steps: Review your AI-generated content strategically with AI detection tools to identify vulnerable pages. Employ a balanced strategy that combines the speed of AI with human insight and personalization. Put a premium on experience, expertise, authoritativeness, and trustworthiness—playing up author qualifications, original research, and firsthand knowledge.

The December 2025 update is a problem that SEO experts can turn to their advantage. It can be an opportunity for innovation rather than a setback. As a segment of your competition will either abandon AI entirely (and lose productivity), or simply rely on AI methods (and run afoul of penalties), the savvy practitioners who blend human expertise with AI tools will enjoy a sustainable competitive advantage.

Google's objective is not to eliminate AI-generated content, but instead to ensure that all content provided to users, regardless of the producer, is both helpful and created by an expert. How to effectively achieve this without compromising scale is the challenge, and masking AI-generated content is the solution that is taking over.

Key Takeaways:

Google announced the third broad core update of 2025 “in December 2025” about quality and expert knowledge. Raw AI content only sites are being hit with traffic drops of 40-60% while sites that manually revise AI do better. Google is always tweaking their algorithm aside from the broad core updates released 4 times a year. Artificial intelligence + humans + expertise is a sustainable competitive advantage in search results. Experience, expertise, authoritativeness, trustworthiness (E-E-A-T) signals have gotten stronger in all types of content.

This information is based on data gathered through December 13, 2025, while Google’s December core update is still being rolled out. Changes to the trends may be seen as the update continues rolling out through the entire three weeks.