Mozilla tls scanner API alternatives

An observatory for TLS configurations, X509 certificates, and more. If it doesn't fit your project, here are the 10 best free Security APIs to use instead in 2026, out of 60 in the directory.

For reference, Mozilla tls scanner API: No API key needed · HTTPS.

1. 1

   Presend API

   Online · 399 ms

   Security and developer utility API -- malware, vulnerability, and domain checks, no signup.

   • No API key needed
   • Fast: 399 ms response
   • Callable from the browser (CORS)
   • HTTPS

   No authHTTPSCORS
2. 2

   IPGuardian API

   Online · 940 ms

   Check IP addresses against 140+ public threat intelligence blocklists.

   • No API key needed
   • Callable from the browser (CORS)
   • HTTPS

   No authHTTPSCORS
3. 3

   IPLogs API

   Online · 762 ms

   Free VPN, proxy, Tor and datacenter IP detection. 13 sources, active probing.

   • No API key needed
   • Callable from the browser (CORS)
   • HTTPS

   No authHTTPSCORS
4. 4

   OSV API

   Online · 608 ms

   Open source vulnerability database and distributed triage infrastructure.

   • No API key needed
   • Callable from the browser (CORS)
   • HTTPS

   No authHTTPSCORS
5. 5

   Passwordinator API

   Online · 730 ms

   Generate random passwords of varying complexities.

   • No API key needed
   • Callable from the browser (CORS)
   • HTTPS

   No authHTTPSCORS
6. 6

   VPNDetection API

   Online · 726 ms

   Check whether an IPv4 or IPv6 address belongs to VPN infrastructure, no key needed.

   • No API key needed
   • Callable from the browser (CORS)
   • HTTPS

   No authHTTPSCORS
7. 7D

   dead-drop API

   Online · 688 ms

   Ephemeral zero-knowledge encrypted data sharing.

   • No API key needed
   • Callable from the browser (CORS)
   • HTTPS

   No authHTTPSCORS
8. 8

   URLhaus API

   Online · 317 ms

   Database of malicious URLs used for malware distribution.

   • No API key needed
   • Fast: 317 ms response
   • HTTPS

   No authHTTPSCORS ?
9. 9

   FilterLists API

   Online · 1008 ms

   Lists of filters for adblockers and firewalls.

   • No API key needed
   • HTTPS

   No authHTTPSCORS ?
10. 10

    Microsoft Security Response Center (MSRC) API

    Online · 1079 ms

    Programmatic interfaces to engage with the Microsoft Security Response Center (MSRC).

    • No API key needed
    • HTTPS

    No authHTTPSCORS ?

Mozilla tls scanner API vs alternatives

Mozilla tls scanner API compared with its alternatives

API	API key	HTTPS	CORS	Uptime	Response	Rating
Mozilla tls scanner	No	Yes	Unknown	Up	989 ms	Not rated
Presend	No	Yes	Yes	Up	399 ms	Not rated
IPGuardian	No	Yes	Yes	Up	940 ms	Not rated
IPLogs	No	Yes	Yes	Up	762 ms	Not rated
OSV	No	Yes	Yes	Up	608 ms	Not rated
Passwordinator	No	Yes	Yes	Up	730 ms	Not rated
VPNDetection	No	Yes	Yes	Up	726 ms	Not rated
Ddead-drop	No	Yes	Yes	Up	688 ms	Not rated
URLhaus	No	Yes	Unknown	Up	317 ms	Not rated

See also: best Security APIs · all Security APIs