SFR IP Lookup

SFR operates the following Autonomous System Numbers (ASNs): AS15557, AS21502. SFR (Société Française du Radiotéléphone) operates AS15557, France's second-largest ISP; SFR's network is notable for early IPv6 FTTH deployments and its CGNAT implementation on legacy DSL lines. Use our IP lookup tool to identify which specific ASN a SFR IP belongs to.

SFR holds multiple IP address blocks allocated by its regional internet registry. These blocks are announced via BGP under AS15557 and AS21502. You can identify SFR IP addresses using our IP lookup tool — enter any IP and check if the ISP/ASN fields show SFR.

Enter the IP address in our IP Lookup tool. The ISP and ASN fields will show whether the IP is registered to SFR (look for AS15557 or AS21502). You can also use our WHOIS Lookup to query the IP's network registration directly from the RIR database.

SFR provides internet services in: France. IP geolocation for SFR addresses shows the registered location of the IP block, which may differ from the user's actual city.

SFR is a mixed (residential + mobile + enterprise) — its customer IPs are generally classified as residential or mobile, not VPN/proxy. However, customers may run VPN servers on SFR IP addresses, which can cause individual IPs to be flagged.