Free SEO spider software
for modern Mac
Crawly is SEO spider software built natively for Mac. Crawl any site, surface every SEO issue, and connect to your AI tool via MCP. No licence fee. No URL cap. No Java.
macOS 12 or later - Apple Silicon and Intel
What is an SEO spider?
An SEO spider is a tool that crawls every page on a website - following links from one URL to the next, just like Googlebot does. For each page it visits, it records data: the page title, meta description, H1 tag, HTTP status code, response time, canonical URL, whether the page is indexable and much more.
SEO professionals use spiders to audit sites for technical issues, check that redirects are set up correctly, verify that important pages are indexable and track how a site changes between crawls. Without a spider, you're relying on manual checks or incomplete reports from tools that only sample your site.
Screaming Frog SEO Spider popularised the category of SEO spider software - but it costs £259 per year for unlimited crawls and requires a Java runtime. Crawly is free, native Mac SEO spider software with no URL cap and a built-in AI integration.
Crawly's issues dashboard - every SEO problem auto-categorised by type and severity.
Everything a free SEO spider should do
And a few things paid ones don't.
Crawls every page
Follows every internal link from your start URL and builds a complete picture of your site - status codes, titles, H1s, meta descriptions, response times and more.
Auto-detects SEO issues
Missing titles, duplicate H1s, broken pages, redirect chains, non-indexable URLs, mixed content - every issue is flagged and grouped automatically.
Image audit
Crawly finds every image on every page and flags missing alt text, oversized files and broken image URLs across the whole site.
Crawl comparison
Run two crawls and diff them. See exactly which pages were added, removed or changed - with field-level diffs for title, H1, status and indexability.
AI-powered analysis via MCP
Connect Crawly to Claude Code, Cursor or Codex via MCP and ask questions like 'which pages are missing a meta description?' directly from your terminal.
Save and reopen crawls
Every crawl is saved locally. Reopen, compare and export at any time - no cloud account required.
Crawly vs Screaming Frog
The most popular SEO spider comparison.
| Feature | Crawly | Screaming Frog |
|---|---|---|
| Price | Free | £259 / year |
| URL limit | Unlimited | 500 (free), unlimited (paid) |
| Platform | Native Mac app | Java (Windows, Mac, Linux) |
| Apple Silicon support | Yes - universal build | Via Java runtime |
| Crawl comparison | Yes | Yes (paid) |
| AI / MCP integration | Yes - Claude Code, Cursor, Codex | No |
| Licence required | No | Yes |
| Local data storage | Yes - fully local | Yes |
Frequently asked questions
What is an SEO spider?
An SEO spider (also called an SEO crawler) is a tool that systematically browses every page on a website - just like a search engine bot would. It collects data about each URL: status codes, page titles, meta descriptions, H1 tags, response times, canonical tags, indexability and more. SEO professionals use spiders to audit sites, find technical issues and track changes over time.
Is Crawly really free?
Yes. Crawly is completely free to download and use with no URL limits. There is no licence fee, no trial period and no paid tier required to unlock features. It will always have a free tier.
How is Crawly different from Screaming Frog SEO Spider?
Crawly is free with no URL cap, while Screaming Frog costs £259/year for unlimited crawls. Crawly is a native Mac app (no Java required), runs faster on Apple Silicon and includes a Claude Code MCP integration for AI-powered analysis. Screaming Frog has more advanced configuration options and supports Windows and Linux.
Does Crawly work on Apple Silicon (M1, M2, M3, M4)?
Yes. Crawly is a universal Mac build that runs natively on both Apple Silicon and Intel Macs - no Rosetta or Java runtime needed.
How many pages can Crawly crawl?
There is no hard limit. Crawly can handle thousands of URLs - performance depends on your machine and the target server's response time.
What SEO issues does Crawly detect?
Crawly detects missing and duplicate page titles, missing and duplicate H1s, missing meta descriptions, missing image alt text, 4xx and 5xx errors, redirect chains, non-indexable pages, mixed content, hreflang errors, near-duplicate content and more.
Start crawling smarter
Download Crawly for free. Connect to Claude Code via MCP and start auditing your site in minutes.
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