Ahrefs vs CrawlZilla

Ahrefs is a web and API platform for SEO research, including keyword research, rank tracking, site audits, backlink analysis and competitor research. It also provides content tools, AI assistants and MCP access. Content Explorer can find web mentions and link prospects, while AI Content Helper supports content improvement. The free plan provides site data and fixes with limited access to Site Explorer and Site Audit. Paid plans start with Starter at $29 a month. Lite costs $129 a month and includes five projects, 750 tracked keywords, 100,000 monthly crawl credits and one user; its Site Audit allowance has a 25,000-page project maximum. Annual payment saves up to 17%. Enterprise costs $1,499 a month and requires an annual commitment; it includes SSO, two-factor authentication, ISO27001 certification, access management, audit logs and unlimited additional users. Ahrefs says its web index contains 170 trillion pages, tracks 41.9 billion keywords and filters 28.7 billion keywords; AhrefsBot crawls 8 billion pages daily. Founded in 2010, the company is headquartered in Singapore. Multilingual support is available five days a week.

CrawlZilla is a cloud-based SEO crawler for technical site analysis, available on the web and through an API. Its Spider, List and Subdomain modes can crawl HTML, images, JavaScript, CSS and PDFs. Each URL can include more than 40 data points, such as titles, canonicals, hreflang, schema and Open Graph information. An internal-link graph tracks links to help identify orphan pages and show PageRank flow; headless Chrome renders JavaScript pages. Lighthouse audits report Performance, Accessibility, Best Practices and SEO scores, plus Core Web Vitals. Page Monitor checks URLs on a chosen schedule, detects changes across 12 or more SEO fields and can send email alerts. Its REST API uses HTTPS, returns JSON and authenticates with bearer tokens. The free plan allows 10,000 URLs per session, 10 requests per second, three Lighthouse audits per crawl and 20 monitored URLs. Premium is £39.99 a month, with limits of 1,000,000 URLs per session, 20 requests per second, 10 Lighthouse audits per crawl and 500 monitored URLs. The maker says its distributed cloud infrastructure supports crawls of 100 million or more URLs and requires no installation or server management.