# Free Threat Intelligence APIs: What's Available and How to Use Them

> Threat intelligence APIs provide programmatic access to indicators, reputation data and context about threats. What free options can do, where they fit, and how to use them well.

Source: https://playciso.com/blog/threat-intelligence-apis-free · Published: 2026-09-26 · Publisher: PlayCISO (https://playciso.com)

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Threat intelligence APIs turn "look this indicator up" into something your tools do automatically — enriching alerts, scoring indicators and supporting hunts at machine speed. You do not need an expensive feed to start: free and freemium options cover a lot of the ground. ## What they provide Programmatic access to threat data: indicators of compromise (malicious IPs, domains, URLs, file hashes), reputation and categorisation, and sometimes context like malware families or campaigns. Free tiers exist across reputation lookups, breach/exposure data and open indicator feeds. ## Where they fit - Alert & log enrichment — add reputation and context so analysts triage faster. - Indicator scoring/blocking — act on known-bad IPs, domains, URLs, hashes. - Threat hunting — search your environment for known-bad artifacts. - Triage automation — feed SOAR playbooks. ## Using them well Match the feed to your use case, understand freshness and false-positive characteristics (stale indicators cause noise and mis-blocks), respect rate limits, avoid over-automating hard blocks on shared/dynamic indicators, and keep API keys server-side and secret. Intelligence is an input to detection and decisions, not an automatic action. Explore endpoints in the free [Security APIs directory →](/security-apis), check indicators with the [Reputation Checker](/tools/reputation-checker), and see adversary context in the [APT Intel Feed](/tools/apt-intel-feed). ## Frequently asked questions **What is a threat intel API?** Programmatic access to IOCs (IPs, domains, URLs, hashes), reputation/categorisation and context. **Are there free ones?** Yes — reputation lookups, breach/exposure data and open feeds have free/freemium tiers. **How is it used?** Alert enrichment, indicator scoring/blocking, threat hunting, triage automation. **Watch out for?** Freshness/false positives, rate limits, over-automation on shared indicators; keep keys secret.