{"uid":"cap_Syh3JFtv04OAu6eKe4197","slug":"is-port-25-open-d116db94","name":"is-port-25-open","description":"Is TCP port 25 (SMTP) open on a host? Attempts a connection from Cloudflare's edge and reports open/closed/filtered with the connect time; Cloudflare-fronted hosts are reported as inconclusive because their edge answers for them. Exposure checks for SMTP without running a scanner. $0.01 per check.","url":"https://ip.intel.rallylive.ca/ip/port/25?utm_source=zero.xyz","method":"GET","headers":{},"bodySchema":{"type":"object","$schema":"https://json-schema.org/draft/2020-12/schema","required":["input"],"properties":{"input":{"type":"object","required":["type","method"],"properties":{"type":{"type":"string","const":"http"},"method":{"enum":["GET"],"type":"string"},"queryParams":{"type":"object","properties":{}}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object"}}}}},"responseSchema":null,"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.01","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"probe","requiresHandshake":false,"reviewCount":0,"rating":{"score":"0.00","successRate":"0.00","reviews":0,"stars":null,"state":"unrated"},"availabilityStatus":"unknown","priceObserved":null,"sessionDeposit":null,"pricing":{"kind":"static","summary":"$0.01/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.01","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.01","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_GJK8Q8MfWoixSSnzmPSm4","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.01","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Checks whether TCP port 25 (SMTP) is open, closed, or filtered on a given host by attempting a connection from Cloudflare's edge network.","exampleAgentPrompt":"Can you check whether TCP port 25 (SMTP) is open or closed on mail.example.com? I want to know if the mail server is exposed without running a scanner myself.","exampleUseCases":[{"title":"Mail server exposure audit","prompt":"Check if port 25 is open on smtp.mycompany.com — I need to know whether our SMTP port is exposed to the internet before our security review."},{"title":"Deliverability troubleshooting","prompt":"Is port 25 open on mx1.clientdomain.com? We're having email delivery issues and I want to verify the SMTP port is actually reachable."},{"title":"New VPS email setup check","prompt":"I just set up a new mail server at 198.51.100.42 — can you check from outside if port 25 is open, closed, or filtered so I know if it's reachable?"}],"resultDescription":"Returns whether TCP port 25 (SMTP) is open, closed, or filtered on the target host, along with the connection time in milliseconds. If the host is behind Cloudflare's edge network, the result is flagged as inconclusive because Cloudflare's infrastructure answers on behalf of the host.","failureModes":["Host behind Cloudflare returns inconclusive result — Cloudflare's edge intercepts the connection","Invalid or unresolvable hostname returns an error","Timeout may cause filtered vs closed ambiguity","Rate limiting or payment failure returns a 402 or error response"],"whenToPreferThis":"Use this endpoint when you need a quick, external vantage-point check of whether TCP port 25 (SMTP) is open on a host without deploying your own scanner. It is especially useful for security audits, mail server setup verification, and deliverability troubleshooting. Prefer this over generic port scanners when you want a lightweight, pay-per-check approach from Cloudflare's edge network.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-13T00:40:42.726Z","isFirstParty":false,"canonicalSlug":"is-port-25-open-d116db94"}