Measurements
buffer.lol returns diagnostic signals rather than a single score. Each tool answers a narrow question about a domain, URL, certificate, network, IP address, or browser-local value.DNS records
DNS lookups show the records published for a domain.A and AAAA records identify IPv4 and IPv6 addresses, MX records identify mail exchangers, TXT records often carry verification and policy data, and NS or SOA records describe delegation and authority.
HTTP status and headers
HTTP checks show the response status, response time from the diagnostics service, and headers. Headers can reveal cache behavior, redirects, content type, server metadata, security policy, and whether a target rejectsHEAD requests.
TLS validity
TLS checks connect to the target host, read the peer certificate, and report authorization state, protocol, cipher, issuer, names, fingerprint, and validity dates. An unauthorized result can point to an expired certificate, hostname mismatch, incomplete chain, or other trust problem.Port reachability
Port checks open a TCP connection from the diagnostics service to a publichost:port. A reachable result means the port accepted a connection from buffer.lol; an unreachable result can mean the service is down, filtered, restricted by firewall rules, or only reachable from another network.
RDAP data
RDAP lookups summarize domain and IP registration data from public RDAP providers. They can include network ranges, country fields, registrar or entity names, nameservers, events, and source links.ASN data
ASN checks use Team Cymru DNS data to connect a public IP address or autonomous system number to origin network records. Results can include ASN, prefix, country, registry, allocation date, and network name.Duration
Server-side API responses includedurationMs. This is the time buffer.lol spent handling that diagnostic request, not a promise about the end user’s network quality.