Top 40 Security APIs For Developers - Public APIs

Application Environment Verification - Android library and API to verify the safety of user devices, detect rooted devices and other risks
BinaryEdge - Provide access to BinaryEdge 40fy scanning platform
BitWarden - Best open-source password manager
Botd - Botd is a browser library for JavaScript bot detection
Bugcrowd - Bugcrowd API for interacting and tracking the reported issues programmatically
Censys - Search engine for Internet connected host and devices
Classify - Encrypting & decrypting text messages
Complete Criminal Checks - Provides data of offenders from all U.S. States and Pureto Rico
CRXcavator - Chrome extension risk scoring
Dehash.lt - Hash decryption MD5, SHA1, SHA3, SHA256, SHA384, SHA512
EmailRep - Email address threat and risk prediction
Escape - An API for escaping different kind of queries
FilterLists - Lists of filters for adblockers and firewalls
FingerprintJS Pro - Fraud detection API offering highly accurate browser fingerprinting
FraudLabs Pro - Screen order information using AI to detect frauds
FullHunt - Searchable attack surface database of the entire internet
GitGuardian - Scan files for secrets (API Keys, database credentials)
GreyNoise - Query IPs in the GreyNoise dataset and retrieve a subset of the full IP context data
HackerOne - The industry’s first hacker API that helps increase productivity towards creative bug bounty hunting
Hashable - A REST API to access high level cryptographic functions and methods
HaveIBeenPwned - Passwords which have previously been exposed in data breaches
Intelligence X - Perform OSINT via Intelligence X
LoginRadius - Managed User Authentication Service
Microsoft Security Response Center (MSRC) - Programmatic interfaces to engage with the Microsoft Security Response Center (MSRC)
Mozilla http scanner - Mozilla observatory http scanner
Mozilla tls scanner - Mozilla observatory tls scanner
National Vulnerability Database - U.S. National Vulnerability Database
OWASP ZAP - Automated security testing API for web apps
Passwordinator - Generate random passwords of varying complexities
PhishStats - Phishing database
Privacy.com - Generate merchant-specific and one-time use credit card numbers that link back to your bank
Pulsedive - Scan, search and collect threat intelligence data in real-time
SecurityTrails - Domain and IP related information such as current and historical WHOIS and DNS records
Shodan - Search engine for Internet connected devices
Spyse - Access data on all Internet assets and build powerful attack surface management applications
Threat Jammer - Risk scoring service from curated threat intelligence data
UK Police - UK Police data
Virushee - Virushee file/data scanning
VulDB - VulDB API allows to initiate queries for one or more items along with transactional bots
Whoisfreaks - Domain and DNS related information that will equip organizaion with comprehensive threat intelligence and attack surface analysis capabilities for enhanced security