Who should use SEO Checker?

SEO Checker is a B2B product built for website owners, SEO professionals, and developers.

Does SEO Checker have a free plan?

Yes — SEO Checker is free to use.

What platforms does SEO Checker run on?

SEO Checker runs on the web, embeddable surfaces, Windows, macOS, and Linux.

Is SEO Checker still active?

Unverified. SEO Checker has not been re-checked since it entered the index, so there is no finding either way — and only a positive finding would say otherwise.

What projects are similar to SEO Checker?

Similar projects tracked by PulseGate include SEO Onpage Checker, SEO Site Auditor, and SEO Backlink Checker Pro.

Who makes SEO Checker?

SEO Checker is developed by Jeff Carpenter.

How long has SEO Checker been around?

SEO Checker first shipped in 2025.

Back to the index

SEO Checker

Name: SEO Checker
Author: Jeff Carpenter

mozilla.orgSEO audit & analysis

SEO Checker is a Firefox browser extension that analyzes websites for SEO-friendliness. It provides a lightweight way for website owners, SEO professionals, and developers to inspect SEO factors while browsing.

FreeWebEmbeddableWindowsmacOSLinux

Visit mozilla.org

7alternatives

4features

2025since

Overview

4 features

In the SEO audit & analysis space, SEO Checker takes a focused approach. It focuses on checking website SEO factors without manually inspecting pages or using separate tools. It is built as a B2B product for website owners, SEO professionals, and developers. SEO Checker costs nothing to use. It ships for the web, embeddable surfaces, Windows, macOS, and Linux.

Behind SEO Checker is Jeff Carpenter, and it first shipped in 2025. PulseGate's similarity index places it among 7 comparable projects. Among its 4 catalogued features are SEO analysis, website checking, and browser extension. The interface is available in 32 languages, including Czech, German, and Greek.

Summary written by a language model from the project’s public pages.

SEO analysis
Website checking
Browser extension
All-site access

Built with & integrations

Runs on

BrowserEmbeddableWindowsmacOSLinux

Trust & compliance

Verified signals

HTTPSPrivacy Policy Terms of ServiceFree tierMulti-languageStore-verified publisher

Legal

Indexing history

What PulseGate has recorded for this listing

Indexed19 Sep · 07:20 UTC
SEO Checker verified via Firefox Add-ons
Source: Firefox Add-ons · Open

Frequently asked questions about SEO Checker

What does SEO Checker do?: SEO Checker focuses on checking website SEO factors without manually inspecting pages or using separate tools. It is catalogued under SEO audit & analysis on PulseGate.
Who should use SEO Checker?: SEO Checker is a B2B product built for website owners, SEO professionals, and developers.
Does SEO Checker have a free plan?: Yes — SEO Checker is free to use.
What platforms does SEO Checker run on?: SEO Checker runs on the web, embeddable surfaces, Windows, macOS, and Linux.
Is SEO Checker still active?: Unverified. SEO Checker has not been re-checked since it entered the index, so there is no finding either way — and only a positive finding would say otherwise.
What projects are similar to SEO Checker?: Similar projects tracked by PulseGate include SEO Onpage Checker, SEO Site Auditor, and SEO Backlink Checker Pro.SEO Onpage Checker SEO Site Auditor SEO Backlink Checker Pro
Who makes SEO Checker?: SEO Checker is developed by Jeff Carpenter.
How long has SEO Checker been around?: SEO Checker first shipped in 2025.

At a glance

Pricing: Free
Platforms: Web
Built for: website owners, SEO professionals, and developers
Model: B2B
Solves: Checking website SEO factors without manually inspecting pages or using separate tools.

Registered as

Firefox Add-ons: seo-checker

Developer

Jeff Carpenter

Index record

Indexed: 19 Sep 2026
Lifecycle: Alive
Last seen: 19 Sep 2026

Identity audit (13)

Slug: seo-checker-mozilla-org
Lifecycle state recorded: 19 Sep 2026
Verification state: Indexed for public listing
Listing state: Listed: yes
Index status: Included in index
Latest evidence snapshot: 19 Sep 2026
Timeline basis: Indexed-at chronology. This listing's first-seen date was written by the catalog backfill, not observed here, so it is not treated as a sighting.
Name from: Derived from the project's own page and URL.
Category from: Assigned by a language model.
Summary from: Written by a language model from public pages.
Languages from: Detected by a language model, checked against the page's own declaration.
Last updated: 19 Sep 2026
Canonical URL: https://addons.mozilla.org/en-US/firefox/addon/seo-checker

Ship this? Send a correction — no account, and you get a link to follow it.

Similar projects

Closest matches by what these projects do