1. SEOquake
Instant on-page SEO audit and SERP metrics overlay.
Why it replaces website broken link and 404 error checker: Covers similar ground in the SEO category: Instant on-page SEO audit and SERP metrics overlay.
Best website broken link and 404 error checker Alternatives in 2026
website broken link and 404 error checker is a strong option, but it is not the right fit for everyone. Below are 10 alternatives compared on rating, install base, pricing and the use case each one actually wins on.
About website broken link and 404 error checker
A SEO tool to fast find all broken links on your websites to Rank Higher.
Free
Full reviewComparison at a glance
| Extension | Rating | Users | Pricing | Best for |
|---|---|---|---|---|
| website broken link and 404 error checker (original) | — | — | Free | A SEO tool to fast find all broken links on your websites to Rank Higher. |
| SEOquake | 4.5 | 1M+ | Free | Anyone who wants a broad SEO toolbar without paying, and is willing to spend ten minutes configuring it |
| Keywords Everywhere | 4.5 | 1M+ | Paid | Keyword research in the flow of browsing, for people happy to buy credits instead of a full platform |
| MozBar | 3.3 | 900K+ | Freemium | Sizing up competitor difficulty at a glance, especially for teams already invested in Moz Pro |
| Detailed SEO Extension | 4.9 | 600K+ | Free | The first extension to install for technical and on-page SEO checks, free and account-free |
| Ahrefs SEO Toolbar | 4.4 | 400K+ | Freemium | SEO professionals who already pay for Ahrefs and want backlink and SERP context without leaving the search results |
| AI SEO Assistant | — | — | Free | One-click SEO prompts for ChatGPT and Claude: keyword strategy, blogs, outrank, AI search, schema and content audits. |
| SEOFOMO News | — | — | Free | Stay updated with the latest SEO trending stories from SEOFOMO News. Get instant notifications about new stories in your browser. |
| Webopt - Website Testing Tool | — | — | Free | All-in-one Chrome extension for SEO, UI/UX, responsive design, grammar, and security checks. Optimize websites with a single click. |
| Image SEO Optimizer: Audit & Optimize Images | — | — | Free | Image SEO Optimizer is an audit tool to optimize website images for search engines: alt text, captions, size & best SEO practices. |
| Squarespace Image Optimzer | — | — | Free | Resize and compress images locally for SEO with Gumroad subscription limits. |
website broken link and 404 error checker alternatives in detail
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2. Keywords Everywhere
Keyword volume, CPC and competition data inside search results.
Why it replaces website broken link and 404 error checker: Covers similar ground in the SEO category: Keyword volume, CPC and competition data inside search results.
3. MozBar
Domain and page authority metrics on every SERP.
Why it replaces website broken link and 404 error checker: Covers similar ground in the SEO category: Domain and page authority metrics on every SERP.
4. Detailed SEO Extension
One-click on-page SEO audit for any URL.
Why it replaces website broken link and 404 error checker: Covers similar ground in the SEO category: One-click on-page SEO audit for any URL.
5. Ahrefs SEO Toolbar
SERP metrics and on-page report from Ahrefs data.
Why it replaces website broken link and 404 error checker: Covers similar ground in the SEO category: SERP metrics and on-page report from Ahrefs data.
6. AI SEO Assistant
One-click SEO prompts for ChatGPT and Claude: keyword strategy, blogs, outrank, AI search, schema and content audits.
Why it replaces website broken link and 404 error checker: Covers similar ground in the SEO category: One-click SEO prompts for ChatGPT and Claude: keyword strategy, blogs, outrank, AI search, schema and content audits.
7. SEOFOMO News
Stay updated with the latest SEO trending stories from SEOFOMO News. Get instant notifications about new stories in your browser.
Why it replaces website broken link and 404 error checker: Covers similar ground in the SEO category: Stay updated with the latest SEO trending stories from SEOFOMO News. Get instant notifications about new stories in your browser.
8. Webopt - Website Testing Tool
All-in-one Chrome extension for SEO, UI/UX, responsive design, grammar, and security checks. Optimize websites with a single click.
Why it replaces website broken link and 404 error checker: Covers similar ground in the SEO category: All-in-one Chrome extension for SEO, UI/UX, responsive design, grammar, and security checks. Optimize websites with a single click.
9. Image SEO Optimizer: Audit & Optimize Images
Image SEO Optimizer is an audit tool to optimize website images for search engines: alt text, captions, size & best SEO practices.
Why it replaces website broken link and 404 error checker: Covers similar ground in the SEO category: Image SEO Optimizer is an audit tool to optimize website images for search engines: alt text, captions, size & best SEO practices.
10. Squarespace Image Optimzer
Resize and compress images locally for SEO with Gumroad subscription limits.
Why it replaces website broken link and 404 error checker: Covers similar ground in the SEO category: Resize and compress images locally for SEO with Gumroad subscription limits.
Compare website broken link and 404 error checker head-to-head
Direct comparisons with the extensions people weigh against it.
Ahrefs SEO Toolbar vs MozBarDomain Rating and traffic estimates behind a paid plan, or Moz's DA and PA on a free community account? The two classic SERP overlays, compared honestly.Ahrefs SEO Toolbar vs SEOquakeThe paid-grade overlay against the most capable free one — same job in the SERP, very different cost and data quality.MozBar vs SEOquakeAuthority scores only, or a full free toolbar with on-page audit, keyword density and domain comparison?All comparisonsThe full compare hub, grouped by category.
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Frequently asked questions
What is the best alternative to website broken link and 404 error checker?
SEOquake is the closest match. Covers similar ground in the SEO category: Instant on-page SEO audit and SERP metrics overlay.
Is there a free alternative to website broken link and 404 error checker?
Yes — SEOquake, Detailed SEO Extension, AI SEO Assistant are free.