Pull backlink data from both Ahrefs API v3 and the Semrush Backlinks API for a cross-verified backlink audit

Steps

1. For Ahrefs, create an API key in Account settings (workspace owner/admin only) and authenticate requests with an Authorization: Bearer header; note keys expire after one year and must be rotated
2. Query the relevant Ahrefs Site Explorer v3 backlinks endpoints for referring domains, backlink lists, and anchor text, applying the documented row-limit and filtering parameters per plan tier
3. For Semrush, call the Backlinks API (v4 analytics/backlinks endpoints, e.g. the overview report) with a target and scope (ROOT_DOMAIN, SUBDOMAIN, SUBFOLDER, or PAGE) parameter
4. Track API unit consumption for Semrush calls before running large jobs, since cost varies by endpoint and row count and can exhaust a plan's balance quickly on wide audits
5. Normalize both providers' output (domain rating/authority scores are provider-specific and not directly comparable) into a common schema keyed by referring domain and target URL
6. Flag backlinks appearing in only one provider's index as lower-confidence signals rather than treating either dataset as a complete crawl of the link graph