Screaming Frog SEO Spider vs Seolyzer in 2026: A desktop crawler you own vs real-time log analysis in the cloud
Screaming Frog crawls locally for a flat £199 a year and includes server log analysis in the box. Seolyzer runs in the cloud, streams Googlebot activity in real time, and fuses crawl, log, and Search Console data into one view, but hides its price behind a demo request.
Screaming Frog SEO Spider
Seolyzer- Screaming Frog includes server log analysis in its standard £199/year license. Seolyzer includes log analysis on all three tiers but reserves cross-analysis, API access, and scheduled crawls for Professional and Enterprise.
- Seolyzer streams Googlebot activity in real time as it happens. Screaming Frog processes uploaded log files in batch, which is a meaningfully different diagnostic speed.
- Screaming Frog has no cloud scheduling; crawls run locally whenever you start them. Seolyzer supports scheduled and recurring crawls on its paid tiers so large sites stay current without a manual re-run.
- Screaming Frog's paid license has no crawl cap at all. Seolyzer does not publish a URL limit and asks enterprise customers to confirm scale directly during the demo.
- Seolyzer's cross-analysis mode fuses crawl data, log activity, and Google Search Console into one view to surface pages that are crawled but not indexed. Screaming Frog has no equivalent fusion feature.
- Screaming Frog supports custom extraction via XPath, CSS, and regex for pulling arbitrary data from page source. Seolyzer's own feature list does not mention custom extraction.
- Seolyzer is GDPR compliant with data hosted in Europe, confirmed explicitly in their own FAQ. Screaming Frog keeps all data local on your machine by design, since it never leaves your hardware.
Screaming Frog SEO Spider and Seolyzer both crawl a site and both analyse server logs, so this is a genuine head-to-head rather than two tools sharing a category tag by accident. The difference is how each one is built and priced. Screaming Frog runs locally on your machine, processes uploaded log files in batch, and costs a flat £199 a year with no crawl cap on the paid license. Seolyzer runs as a cloud platform, streams Googlebot activity in real time, and fuses crawl data, log activity, and Google Search Console into a single cross-analysis view, but does not publish pricing on any of its three tiers and routes everyone through a demo request. One is a tool you buy and run yourself; the other is a platform you subscribe to and are sold into.
The tools at a glance
Screaming Frog SEO Spider
The industry-standard desktop crawler for technical SEO audits.
Screaming Frog crawls from your own machine, not someone else's cloud, which means your data never leaves your hardware and crawl speed is a function of your own specs. The free tier caps out at 500 URLs; the paid license removes that limit completely for £199 a year and adds JavaScript rendering, custom extraction, and direct Google integrations.
Server log analysis is included in the standard license, which is unusual since several competitors treat it as a separate add-on or an enterprise-only feature. Upload Apache, Nginx, or IIS logs and the Spider maps Googlebot activity against your site structure so you can see exactly where crawl budget is being wasted, though the analysis works on files you upload after the fact rather than a live stream.
What it does not do is run in the cloud. There is no scheduled crawling without a machine sitting on and running the app, no shared team dashboard, and no way to license a single seat across a distributed team without buying multiple licenses. It rewards people who want direct control over the crawl and are comfortable working with raw exports.
| Feature | Free Free (limited to 500 URLs) | Single License £199/year | 5-9 Licenses £189 per license/year | 10-19 Licenses £179 per license/year | 20+ Licenses £169 per license/year |
|---|---|---|---|---|---|
| URL limit | 500 | Unlimited | Unlimited | Unlimited | Unlimited |
| Server log analysis | No | Yes | Yes | Yes | Yes |
| JavaScript rendering | No | Yes | Yes | Yes | Yes |
| Custom extraction | No | Yes | Yes | Yes | Yes |
Seolyzer
Technical SEO data platform combining site crawling, real-time log analysis, and Google Search Console in one interface
Seolyzer is a French technical SEO platform that treats crawling, server log analysis, and Google Search Console as three views of the same underlying question: what is actually happening to your site in Google's eyes. Instead of running these checks separately and comparing spreadsheets by hand, Seolyzer's cross-analysis mode merges them into a single view that surfaces pages Googlebot is ignoring, pages GSC shows impressions for that never actually get crawled, and other mismatches that only become visible once the three data sources are lined up.
The log analysis module is real-time, not batch. Server activity streams in as it happens, so a migration or crawl budget fix shows up in the data immediately instead of waiting for a scheduled import. Client references on the public site, Club Med and ManoMano among them, along with a public endorsement from Aleyda Solis, point to genuine enterprise usage rather than a feature list built for a landing page.
The trade-off is access and learning curve. There is no public pricing on any of the three tiers, Starter, Professional, or Enterprise, and the primary call to action is a demo request rather than a signup form. The tool also assumes you already understand log file formats and Googlebot behaviour; teams new to log analysis will find the interface functional but not built to teach the concepts along the way.
| Feature | Starter Contact for pricing | Professional Contact for pricing | Enterprise Contact for pricing |
|---|---|---|---|
| SEO Crawler | ✓ | ✓ | ✓ |
| Log analysis | ✓ | ✓ | ✓ |
| Cross-analysis (data fusion) | ✗ | ✓ | ✓ |
| API access | ✗ | ✓ | ✓ |
| Scheduled / recurring crawls | ✗ | ✓ | ✓ |
Head-to-head feature comparison
| Feature | Screaming Frog SEO Spider | Seolyzer |
|---|---|---|
| Deployment model | Desktop app (Windows, macOS, Linux) | Cloud platform |
| Pricing model | Flat annual license | Sales-led, contact for pricing on all tiers |
| Server log analysis | Yes, included in standard license | Yes |
| Real-time log streaming | No (batch log upload, not live streaming) | Yes, in real time |
| Site crawler | Yes | Yes |
| Cross-analysis (crawl + logs + GSC fusion) | No | Yes (its most distinctive capability) |
| JavaScript rendering | Yes (paid license) | Not stated in Seolyzer's published feature list |
| Custom data extraction | Yes (XPath, CSS, regex) | Not stated in Seolyzer's published feature list |
| Scheduled / recurring crawls | No (manual re-crawl, no cloud scheduling) | Yes (Professional and Enterprise tiers) |
| API access | No dedicated API; integrates with GSC, GA, and PageSpeed | Yes (Professional and Enterprise tiers) |
| Google Search Console integration | Yes | Yes, on all tiers |
| Google Analytics integration | Yes | Not stated in Seolyzer's published feature list |
| GDPR / EU hosting | Not applicable, data stays local on your machine | Yes, GDPR-compliant EU hosting |
| Starting price | Free / £199/yr | Contact for pricing |
Which should you choose?
Screaming Frog SEO SpiderSeolyzerScreaming Frog SEO SpiderSeolyzerScreaming Frog SEO SpiderSeolyzerScreaming Frog SEO SpiderBoth tools crawl and both analyse logs, so the decision genuinely comes down to depth versus ownership. Seolyzer's real-time cross-analysis is a meaningfully different capability from anything Screaming Frog offers, since fusing live log activity with crawl and GSC data in one view catches problems a batch workflow would only surface days later. Screaming Frog wins on price, ownership of your data, and access: no demo, no sales call, unlimited crawling for a fixed annual fee. Pick Seolyzer when the scale and stakes justify an enterprise contract and real-time visibility; pick Screaming Frog when a capable, affordable, self-directed crawler is enough.
Bottom line
Buy the Screaming Frog license if you want unlimited crawling, included log analysis, and full control over your data for a flat £199 a year with no sales process. Book the Seolyzer demo if you are running enterprise-scale sites where real-time Googlebot visibility and a fused crawl-log-GSC view justify a custom contract and you are comfortable with pricing that is not public until you talk to them. For most freelancers and small-to-mid agencies, Screaming Frog covers the job at a fraction of the cost; Seolyzer earns its price at genuine enterprise scale.
Frequently asked questions
Is Seolyzer worth it over Screaming Frog if I already do log analysis manually?
Only if the delay in batch log analysis is actually costing you time, for example during a migration or a live crawl budget emergency where you need to see Googlebot activity as it happens rather than after an upload. If checking logs periodically after the fact is fast enough for your workflow, Seolyzer's real-time streaming and cross-analysis may not justify the jump to an enterprise contract.
Can Screaming Frog do real-time log streaming the way Seolyzer does?
Screaming Frog analyses server logs you upload after the fact, in batch, not as a live stream, so it cannot match Seolyzer here. Seolyzer is built specifically around real-time log streaming, which is one of its core differentiators. If live Googlebot visibility is the requirement, Screaming Frog cannot deliver that on its own.
Does Seolyzer offer a free trial like Screaming Frog's free crawler tier?
Seolyzer does not advertise a free tier or self-serve trial anywhere on its public site; the primary path to access is a demo request, which suggests pricing is discussed through a sales conversation. Screaming Frog, by contrast, has a genuinely usable free tier capped at 500 URLs per crawl.
Do Screaming Frog or Seolyzer track AI search visibility or AI Overviews?
No, neither tool tracks AI search visibility. Seolyzer states this explicitly in its own FAQ, focusing entirely on traditional crawl, log, and Search Console health. Screaming Frog is the same: a crawler for technical SEO, not an AI visibility monitoring tool.
How does Seolyzer's cross-analysis feature actually help with crawl budget problems?
Cross-analysis fuses crawl data, real-time log activity, and Google Search Console into one view, so you can see pages that are crawled but not indexed, or pages GSC shows impressions for that Googlebot rarely visits. That kind of discrepancy is invisible in any single data source and normally requires manually comparing three separate exports.
Is Screaming Frog's custom extraction feature something Seolyzer also offers?
Screaming Frog supports custom extraction via XPath, CSS selectors, and regex, letting you pull arbitrary data like prices or review counts from page source during a crawl. Seolyzer's published feature list does not include an equivalent custom extraction capability, so this remains a distinct advantage for Screaming Frog.