Does Grammarly Sell Your Typed Data to Advertisers? The Truth About Browser Extension Privacy

Apr 2, 2026

I stared at my Pi-hole dashboard in disbelief. Grammarly was hitting my network with over 250,000 requests per day. That’s roughly 173 requests every minute, or almost 3 requests per second.

The Reddit post I’d read was right: “Grammarly has access to everything on every site.” But was it true that they “instantly sell everything you type to advertisers”?

I needed to find out the truth.

The Alarming Discovery

It started when I set up Pi-hole to block ads and track network traffic. Looking at the query logs, Grammarly dominated the list:

rank  domain                 queries/day
1     f-log.grammarly.com    89,234
2     data.grammarly.com     67,891
3     log.grammarly.com      45,123
4     s.grammarly.com        31,456
5     analytics.grammarly.com 16,298
                              --------
      Total:                 250,002

Every keystroke I typed triggered multiple network calls. Grammar checking, style suggestions, telemetry data—all flowing to their servers.

But here’s the question that mattered: Where does this data go?

What I Found in the Privacy Policy

I went straight to Grammarly’s official privacy policy (updated October 29, 2025). Here’s what they state:

“We make money when users purchase our paid products and not by selling or monetizing user content.”

They also explicitly say:

“We do not use your user content for marketing or advertising purposes.”

“We do not make user content available to these companies [advertising partners].”

So the direct answer is: No, Grammarly does not sell your typed content to advertisers.

But wait—if that’s true, why all the network traffic? And what about the “targeted advertising” section in their policy?

Grammarly’s privacy policy mentions “sales,” “sharing,” and “targeted advertising” under State Privacy Laws. This sounds alarming at first.

Here’s what they actually share:

Data Type              Shared with Advertisers?    Purpose
─────────────────────────────────────────────────────────────
Typed text (content)   NO                          Grammar analysis
Email/Name            NO                          Account management
IP/Device info        NO                          Security
Cookie IDs            YES                         Grammarly's own ads
Email-derived IDs     YES                         Grammarly's own ads

The “sharing” refers to cookie IDs and unique identifiers derived from email addresses. Grammarly uses these to show you ads for Grammarly itself on other platforms—not to sell your typed content.

This is standard practice. Many companies do this. It’s how you see Grammarly ads after visiting their site.

Why the 250,000 Requests?

The massive request volume stems from how Grammarly works:

Real-time analysis: Every keystroke triggers grammar checking
Style suggestions: Contextual recommendations need server queries
Plagiarism detection: Cross-references vast databases
Feature telemetry: Usage analytics for product improvement

This isn’t data selling—it’s the cost of cloud-based grammar checking.

But the volume reveals something important: all your text goes to their servers.

The Real Risk (It’s Not Data Selling)

While Grammarly doesn’t sell your content, genuine privacy concerns remain:

1. Universal Access Scope

Browser extensions request permission to access all websites. Grammarly needs this to function, but it means the extension can read:

Password fields (before they’re masked)
Private emails
Confidential documents
Financial information

2. Cloud Processing Requirement

All text must travel to Grammarly’s servers for analysis. This creates:

Transit exposure risks
Server-side storage (up to 24 hours for documents)
Potential breach targets

3. Trust Dependency

You’re trusting that:

Grammarly follows their stated policies
Their security practices are robust
No rogue employee accesses data
No breach exposes cached content

4. Breach Potential

Cloud services get breached. Even if Grammarly deletes your text after 24 hours, temporary storage creates a window of vulnerability.

What You Can Do About It

Option 1: Restrict Extension Scope

In Chrome, limit Grammarly to specific sites:

Settings > Extensions > Grammarly > Site access

Change from: "On all sites"
Change to:   "On specific sites"

Add only: docs.google.com, gmail.com, notion.so

This prevents Grammarly from seeing sensitive sites like banking portals.

Option 2: Block with Pi-hole

If you want to block Grammarly entirely (or see what’s being collected):

# Block specific endpoints
pihole deny f-log.grammarly.com
pihole deny data.grammarly.com
pihole deny log.grammarly.com
pihole deny s.grammarly.com
pihole deny analytics.grammarly.com

# Or use regex to block all subdomains
pihole regex '\.grammarly\.com$'

Option 3: Opt Out of AI Training

Grammarly uses your content to train AI models by default. You can disable this:

Grammarly Account Settings > Privacy > AI Training > Toggle OFF

Option 4: Use Local Alternatives

For highly sensitive documents, consider offline tools:

LanguageTool (open source, self-hostable)
Vale (command-line linter)
Built-in grammar checkers in word processors

Common Misconceptions

Misconception 1: “No Selling Means No Risk”

False. Even without selling to third parties, your data traverses networks and cloud infrastructure. A breach could expose cached content.

Misconception 2: “Free Extensions Are Free”

You pay with data. Grammarly’s free tier collects usage data. Their business model is upselling paid subscriptions—not selling your text—but data collection enables their product.

Misconception 3: “Private Mode Protects Me”

Browser incognito mode doesn’t prevent extensions from reading content. Grammarly works the same in private windows.

The Verdict

Does Grammarly sell your typed content to advertisers? No.

Should you still be careful? Yes.

The 250,000 daily requests represent legitimate grammar-checking traffic, not data brokerage. Grammarly’s business model depends on subscription revenue, and their privacy policy explicitly prohibits selling user content.

However, the architecture requires trusting a third party with everything you type. For casual writing, that’s acceptable. For confidential documents, consider alternatives.

My Recommendation

I still use Grammarly—but with boundaries:

Restricted site access: Grammarly only runs on document editors
AI training off: My writing doesn’t train their models
Sensitive documents excluded: Financial and legal docs get checked locally
Pi-hole monitoring: I watch for unusual traffic spikes

The lesson isn’t “don’t use Grammarly.” It’s understand what you’re trading for convenience, and set appropriate boundaries.

Browser extensions are powerful tools. They’re also potential surveillance vectors. Pi-hole gave me visibility into what was happening. Grammarly’s policy gave me assurance about their practices.

Both perspectives matter.

Final Words + More Resources

My intention with this article was to help others share my knowledge and experience. If you want to contact me, you can contact by email: Email me

Here are also the most important links from this article along with some further resources that will help you in this scope:

Oh, and if you found these resources useful, don’t forget to support me by starring the repo on GitHub!