FreeSEOCrawlerTool:OurScreamingFrogAlternative

TL;DR: We built a free, open-source SEO crawler tool that does 85-90% of what Screaming Frog does - in an evening. No £200 annual license. No desktop app bloat. Just pure command-line power for developers who want speed and ease. "

Let me tell you about a conversation that happens at agencies everywhere, probably including yours:

Client: "Can you audit our site's SEO?"

Us: "Absolutely! Let me just fire up our SEO crawler tool..."

Finance: "That's £200/year per seat for Screaming Frog."

Us: "...or I could manually check a few pages?"

For years, we've been making these compromises. Not because we're lazy. Not because we don't care about technical SEO audits. But because building a comprehensive website crawler from scratch was the kind of project that would sit in the "someday" folder forever, gathering dust next to "rewrite the company website" and "organise that team building event we keep talking about."

Then AI Changed the Game

Here's the thing about 2025 right now; that still feels slightly surreal: the tools have finally caught up to our ambitions.

I'm not talking about AI writing your content or generating blog posts that sound like they were written by an enthusiastic but slightly confused intern. I'm talking about AI as a force multiplier for developers. Tools like Cursor and Claude that turn "I wish we had a tool that..." into "I built a tool that..." in hours instead of weeks.

So we asked ourselves: what if we just... built our own free SEO crawler?

Not an AI-powered "smart" analyser that tries to guess what Google wants. Not a chatbot that explains SEO to you. A raw, comprehensive, technical SEO auditing tool that does the unglamorous work of crawling every page, extracting every meta tag, checking every heading hierarchy, and flagging every issue - the kind of open-source SEO tool that would have taken a dedicated developer weeks to build in the before-times.

Meet SEO Reporter: The Free Screaming Frog Alternative We Built in a Weekend

SEO Reporter is what happens when you stop asking "can we afford Screaming Frog?" and start asking "what would we build if we had unlimited time?"

It's a TypeScript CLI tool that crawls websites, performs 220+ technical SEO checks, and generates beautiful HTML reports and CSV exports. Think Screaming Frog's core functionality as a command-line SEO tool, minus the desktop app, minus the annual license, plus the warm fuzzy feeling of owning your own tools.

What This SEO Analysis Tool Actually Does

The unglamorous truth about SEO auditing is that most of it is just... checking things. Lots of things. Systematically. The kind of work humans are terrible at and computers excel at:

• Meta tag analysis: Titles, descriptions, canonicals, robots directives - with pixel-width calculations because character counts lie
• Content quality checks: Duplicate detection (exact and near-duplicate using MinHash), thin content, readability scores, even lorem ipsum detection (you'd be surprised)
• Technical SEO: Heading hierarchy, image alt text, internal linking structure, orphan pages, redirect chains
• Security analysis: HTTPS implementation, mixed content, security headers, insecure forms
• URL quality: Because someone on your team definitely used spaces in a URL at some point
• Performance metrics: Response times, HTML size, content-to-code ratios

The Developer-First Approach to Website Crawling

Here's where it gets interesting. We didn't build this as a SaaS product or a desktop app. We built it as a command-line SEO crawler because:

1. Developers live in terminals - Why context-switch to a GUI when you can pipe results directly into your workflow?
2. Automation is trivial - Run it in CI/CD, schedule it as a cron job, integrate it into deployment pipelines
3. Data export is built-in - CSV exports for every data type, ready for Excel, Google Sheets, or your data warehouse
4. No installation headaches - It's an npm package. npx seo-reporter --url https://yoursite.com and you're off

# Basic SEO audit
npx seo-reporter --url https://antler.digital

# Deep crawl with CSV export
npx seo-reporter --url https://yoursite.com \
  --depth 5 \
  --max-pages 2000 \
  --export-csv

# Fast scan for quick technical checks
npx seo-reporter --url https://staging.example.com \
  --depth 2 \
  --concurrency 20

Why This Free SEO Tool Matters More Than You Think

The real story here isn't "we built a Screaming Frog alternative" - plenty of teams build internal tools. The real story is what becomes possible when the barrier to building drops from "weeks of dev time" to "a weekend project".

The Old Way: Tool Poverty

Before AI-assisted development became genuinely useful, agencies operated under what I call "tool poverty." You had two choices:

1. Buy commercial SEO analysis tools - Expensive, often overkill, sometimes vendor lock-in
2. Make do without - Manual processes, spot checks, hoping nothing breaks

The middle ground - building custom website crawlers perfectly suited to your workflow - was too expensive. A custom SEO crawler might take 40-80 hours of developer time. At agency rates, that's £4,000-8,000 of billable hours. Suddenly that £200/year Screaming Frog license looks very reasonable.

The New Way: Tool Abundance

With AI pair programming, the economics flip. Our free SEO crawler represents perhaps 8-10 hours of actual development time, most of it spent on design decisions rather than implementation details. The AI handles:

• Boilerplate TypeScript setup
• HTML parsing logic
• Concurrency management
• CSV export formatting
• Report template structure

We handle:

• What technical SEO checks to perform
• How to categorize issues
• Report design and UX
• Architecture decisions

The result? An open-source SEO tool that's perfectly tailored to how we work, costs nothing to run, and can be extended or modified whenever we need something new.

The Technical Bits (For the Nerds)

If you're still reading, you're probably wondering "yeah, but how does this SEO crawler tool actually work?"

Architecture Philosophy

We kept it brutally simple:

1. Crawler - Breadth-first website crawling with configurable depth and concurrency
2. Parser - Cheerio-based HTML extraction (fast, no browser overhead)
3. Analyzer - Rule-based issue detection with severity categorisation
4. Reporter - Handlebars templates generating self-contained HTML

No databases. No external dependencies in the reports. No JavaScript rendering (yet - that's a future enhancement). Just fast, reliable, static HTML analysis for technical SEO audits.

What We Learned Building a Screaming Frog Alternative

Building a competing SEO analysis tool taught us something valuable: Screaming Frog is actually really good at what it does. Their desktop app is polished, their crawling is sophisticated, their feature set is comprehensive.

But here's what we also learned: For 85-90% of technical SEO audits, you don't need all of that. You need:

• Reliable website crawling
• Comprehensive meta tag extraction
• Clear issue reporting
• Easy data export

And those four things? Totally achievable in a weekend with AI assistance when building your own SEO crawler.

The Real Win: Ownership of Your SEO Tools

The £200 saved on a Screaming Frog license is nice. But it's not the point.

The point is agency autonomy. When you own your SEO crawler tool:

• Client requests become opportunities - "Can you check X?" becomes "Let me add that to our crawler"
• No vendor roadmaps - Want a new technical check? Add it. Want different report styling? Change it
• Integration possibilities - Your tool, your data, your infrastructure
• Learning investment - Every enhancement teaches your team something new

This is what's possible now. Not "someday when we have time." Not "if we can justify the dev cost." Now. This weekend. With AI assistance.

How to Use This Free SEO Crawler (Because You Should)

SEO Reporter is fully open-source and available on npm: npmjs.com/package/seo-reporter

# Quick start - no installation needed
npx seo-reporter --url https://yoursite.com

# Or install this command-line SEO tool globally
npm install -g seo-reporter

# Run a technical SEO audit
seo-reporter --url https://yoursite.com --export-csv

# View the results
open seo-report/index.html

The generated SEO audit reports include:

• Interactive dashboard - Sortable tables, filterable content, severity-based categorization
• Individual page reports - Every meta tag, every heading, every link, every image
• CSV exports - All data, ready for your spreadsheet tool of choice
• Zero dependencies - Self-contained HTML files you can email, archive, or host anywhere

The Meta Point

This blog post is about a free SEO analysis tool. But it's really about what becomes possible when AI removes the implementation barrier from good ideas.

How many tools have you wished existed? How many times have you thought "wouldn't it be great if..." and then moved on because building a custom SEO crawler wasn't feasible?

That calculation has changed. The tools we've wished for - the perfectly tailored, exactly right solutions - are suddenly buildable. Not by compromising with what's commercially available. By making what we actually need.

SEO Reporter is our first experiment in this new paradigm. It won't be our last.

Try This Free Screaming Frog Alternative Yourself

Seriously. Run this open-source SEO tool on your site right now:

npx seo-reporter --url https://yoursite.com

It's free. It's open source. It's a starting point for whatever SEO tooling your team actually needs. Whether you need basic website crawling or comprehensive technical SEO checks, this command-line tool delivers.

And if you find it useful - or if you build something better - we'd love to hear about it. That's the point of all this.