Screaming Frog SEO Spider vs OctopusOn SEO Crawler
Looking for a free Screaming Frog alternative? OctopusOn SEO Crawler is a free, open-source SEO spider for Windows, macOS and Linux. Here is how the two compare, feature by feature.
OctopusOn SEO Crawler vs Screaming Frog SEO Spider
Screaming Frog SEO Spider is the best-known desktop crawler. OctopusOn SEO Crawler covers the core of a technical SEO audit for free and in the open.
| Feature | OctopusOn SEO Crawler | Screaming Frog SEO Spider |
|---|---|---|
| Price | Free, $0; there is no paid version | Free up to 500 URLs; £199 / $279 per user per year |
| URLs per crawl | No limit (memory and disk only) | 500 free; unlimited with a licence |
| Source code and licence | Open source, MIT or Apache-2.0 | Proprietary |
| Account or licence key | None needed | Licence key for the paid version |
| Windows, macOS and Linux | Yes | Yes |
| Spider and list mode | Yes, with TXT, CSV and TSV import | Yes |
| JavaScript rendering | With your installed Chrome or Edge | Paid version |
| Save and reopen crawls | Yes | Paid version |
| Crawl comparison | 30 SEO fields plus findings | Yes |
| Overall SEO score | 0–100, every deduction explained | Issues with high, medium and low priority |
| Broken links, redirects, canonicals, hreflang | Yes | Yes |
| Duplicate and near-duplicate content | Exact groups and SimHash near-duplicates | Yes |
| Structured data validation | JSON-LD for common rich result types | JSON-LD, Microdata and RDFa |
| XML sitemap generator | Yes | Yes |
| Exports | Excel, CSV, JSON | Excel, CSV, Google Sheets |
| Command line | octopuson-crawler | Yes |
| Search Console and Analytics data | SEO Opportunities report (Search Console, GA4) | Paid version (API integrations) |
| Custom extraction (XPath, CSS, regex) | Not yet | Paid version |
| PageSpeed Insights and Core Web Vitals | Not yet | Paid version (API) |
| Built-in scheduling | With your system's scheduler and the command line | Yes |
| Spelling and grammar, crawl visualisations | Not yet | Yes |
Screaming Frog details come from screamingfrog.co.uk (SEO Spider 24.3 and its pricing page), checked on 18 October 2026; prices and features may change. Screaming Frog and SEO Spider are trademarks of Screaming Frog Ltd. OctopusOn is not affiliated with or endorsed by Screaming Frog.
No 500-URL limit, no licence
The free version of Screaming Frog stops at 500 URLs per crawl. OctopusOn SEO Crawler has no paid version, so every feature and every URL is free.
- No licence key, account or renewal
- A URL limit of 0 means unlimited
- Use it for every client and every site
JavaScript SEO included
Rendering is free and uses the Chrome or Edge already on your computer.
- Raw vs rendered title, canonical, directives, words and links
- Desktop, mobile or custom viewport
- Flags a noindex removed by JavaScript
A site audit you can explain to clients
One 0–100 SEO score, built from 100+ checks in 21 categories.
- Every deduction leads to the URLs behind it
- Every finding comes with an explanation and a fix
- Prioritised fixes grouped into nine systems
Open source and private
The code is on GitHub under MIT or Apache-2.0, and crawls stay on your computer.
- Read, audit or extend the code
- Crawl data is never uploaded
- A command line for servers and CI
When Screaming Frog may suit you better
We want you to pick the right tool. Today, Screaming Frog SEO Spider is ahead in these areas:
- Custom extraction with XPath, CSS selectors and regex
- PageSpeed Insights, Core Web Vitals and link metric integrations (Ahrefs, Majestic, Moz)
- Built-in scheduling, crawl visualisations and spelling and grammar checks
- A long track record, vendor support and plenty of training material
Screaming Frog alternative questions
Is there a free alternative to Screaming Frog SEO Spider?
Yes. OctopusOn SEO Crawler is free and open source, with no URL limit. It runs on Windows, macOS and Linux and covers spider and list crawls, JavaScript rendering, broken links, redirects, canonicals, hreflang, duplicates, structured data, XML sitemaps and exports.
Can I crawl more than 500 URLs for free?
Yes. The free version of Screaming Frog is limited to 500 URLs per crawl; OctopusOn SEO Crawler has no URL limit. Very large sites are bound only by your computer's memory and disk.
Does it render JavaScript like Screaming Frog?
Yes. It renders pages with the Chrome, Chromium or Edge on your computer and compares raw and rendered HTML. In Screaming Frog, JavaScript rendering is part of the paid licence.
Can I use both?
Yes. You can keep Screaming Frog for custom extraction and use OctopusOn for free audits, client sites and automation. Both export to CSV and Excel.
Is OctopusOn affiliated with Screaming Frog?
No. OctopusOn is an independent open-source project. Screaming Frog and SEO Spider are trademarks of Screaming Frog Ltd.
Try the free Screaming Frog SEO Spider alternative
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