Guides · 5 min read · Updated 2026-09-08

Screaming Frog alternative: Truelint compared, with measurements

A measured comparison of Truelint and Screaming Frog SEO Spider on the same 20,000-URL site: speed, memory, checks, price, and what each one is better at.

Screaming Frog SEO Spider has been the default technical SEO crawler since 2010, and for good reason: it does almost everything, it’s cheap for what it does, and every SEO already knows its tabs. Any alternative has to be honest about that. This page is a measured comparison, not a takedown; the numbers come from running both tools on the same site on the same laptop, and the feature table lists what Screaming Frog does that Truelint doesn’t.

The short version

Truelint is a desktop crawler with the same shape as Screaming Frog — tabs, filters, an issues list, exports — built in 2026 rather than 2010. That shows in three places: it’s much faster and uses a fraction of the memory, every check tells you how to fix the problem, and the same engine runs from the terminal or in a browser. It’s missing the integrations that need your Google credentials, and it has been around for months rather than years.

If you crawl small sites occasionally, either tool is fine and Screaming Frog is the safer choice today. If you crawl large sites, run crawls in CI, or spend your day explaining audit findings to developers, Truelint was built for you.

Speed and memory, measured

Both tools crawled the same locally served site of 20,000 HTML pages, with the same concurrency (five threads), JavaScript rendering off, on a MacBook Pro with 16 GB. Screaming Frog was version 22.2 with its default memory allocation.

The gap comes from architecture, not tricks. Truelint writes every page to a single SQLite file as it goes and keeps only the in-flight requests in memory, so memory grows with concurrency, not with site size. Screaming Frog keeps its working set in Java heap by default and offers a database mode you switch on for large sites. We also ran Truelint alone on a synthetic one-million-URL site: 307 seconds, 210 MB peak. Screaming Frog can crawl a million URLs too, but its own documentation asks for database storage and a machine with more than 16 GB of RAM to do it comfortably.

The honest caveat: a local fixture removes network latency, which dominates real crawls. On a real site with a 200 ms server, both tools spend most of their time waiting, and the difference narrows to how many requests each can keep in flight. The memory difference does not narrow.

What Truelint checks that Screaming Frog also checks

Almost everything on the classic list: response codes, redirect chains and loops, page titles and meta descriptions (missing, duplicate, too long, too short, multiple), H1 and H2, images without alt text and oversized images, canonicals (missing, non-indexable, conflicting with directives), noindex and nofollow directives, hreflang (missing return links, invalid codes, conflicts), XML sitemap coverage and orphans, duplicate and near-duplicate content, thin content, soft 404s, insecure forms and mixed content, security headers, URL hygiene, pagination, AMP, structured data validation, JavaScript rendering with raw-versus-rendered diffs, custom extraction with CSS, XPath and regex, custom source-code search, custom JavaScript, spelling and grammar, accessibility with axe-core, mobile usability, crawl comparison, XML sitemap generation, scheduled crawls, forms-based login, and site visualisations.

What Screaming Frog has that Truelint doesn’t

• Google Search Console, Google Analytics and PageSpeed Insights integrations. These join your traffic and Core Web Vitals data onto the crawl. They’re on Truelint’s roadmap and need Google OAuth credentials to build.
• Link metrics from Ahrefs, Moz and Majestic. Same situation.
• Looker Studio reporting.
• Fifteen years of edge cases. Screaming Frog has seen every strange server on the internet. Truelint has been validated on a few dozen real sites; it will hit things it hasn’t seen.

What Truelint does differently

Every check explains the fix. Screaming Frog tells you a canonical is missing; Truelint tells you that, why it matters for a page with URL parameters, and what tag to add. The wording was written for the developer who has to make the change. In practice this is the difference between an audit spreadsheet that gets actioned and one that gets filed.

The main content is measured, not the whole page. Word counts, duplicate detection and readability run on the article body, with navigation, headers, footers and sidebars removed. A documentation site with a large shared sidebar shows up as duplicate content in tools that hash the whole page; it doesn’t here.

No rule reports a URL that was never fetched. Sitemap entries the crawl didn’t reach are listed as sitemap findings, not as pages with missing titles. This sounds small until you’ve explained 68,000 false “missing H1” rows to a client.

Three front doors, one engine. The desktop app, the truelint command-line tool and the self-hosted browser interface share the same crawler and the same crawl files. Run a crawl in CI from the terminal, open the result in the app, schedule the next one on a server.

Crawls are single files. A .crawl file is a SQLite database. Open it in the app a year later, diff it against today’s crawl, or query it directly with any SQLite client.

Open core. The crawler and CLI are Apache-2.0 on GitHub. You can read what a check does before you trust it.

Price

Screaming Frog is free up to 500 URLs and £199 a year for unlimited crawling and the integrations. Truelint is free up to 1,000 URLs per crawl with every check included, and Pro is $149 a year for unlimited URLs, crawl comparison and clean exports.

Who should switch, and who shouldn’t

Switch if you audit large sites, if memory has been the reason your crawls fail, if you want crawls in a pipeline, or if you hand findings to developers. Stay with Screaming Frog if your workflow depends on the Search Console or Analytics joins today, or if you need a tool that has already seen every server on earth.

Or run both. Crawls are cheap; opinions are what cost money.

Looking at Sitebulb instead? That comparison is here.