If you need SEO data in your application, you have options — but they vary wildly in price and complexity. Here's an honest comparison.
Moz offers Domain Authority, Page Authority, and link data. Great for backlink analysis but doesn't do on-page SEO auditing. Their API requires OAuth and is oriented toward enterprise users. Minimum $99/mo for 200 rows/month.
Ahrefs is the gold standard for backlink data and keyword research. Their API is powerful but complex, with multiple endpoints for different data types. Starts at $99/mo. Best for agencies with existing Ahrefs subscriptions.
SEMrush covers keyword research, competitor analysis, and site auditing. Their API requires a Guru plan ($119/mo minimum) and has per-unit pricing on top. Enterprise-focused.
Google's own performance analysis tool. Free with a 25,000 requests/day limit. Focuses on Core Web Vitals and performance, not SEO content issues. Great for performance but doesn't check meta tags, headings, or structured data.
Desktop app, not really an API. Excellent for crawling entire sites but requires manual operation. No programmatic access for integration into your apps.
SEO Score API is built for developers who need on-page SEO auditing without the enterprise price tag.
| Feature | SEO Score API | Moz/Ahrefs/SEMrush |
|---|---|---|
| Starting price | Free (5/day) | $99-119/mo |
| On-page SEO checks | 28 checks | Varies |
| Setup complexity | 1 header, 1 endpoint | OAuth, multiple endpoints |
| Backlink data | No | Yes |
| Keyword research | No | Yes |
| Score monitoring | Yes (from $5/mo) | Varies |