On this page

Links, websites & email

Check a link

API · Pro

Coverage: Checks wording and visible links only. The sender, attachments and website contents are not verified.

Open tool
On this page

Purpose

Check numbers, messages and links

Checks wording and visible links only. The sender, attachments and website contents are not verified.

Requirements

Anyone can read these guides, no account needed. Some tools require Pro, as indicated in each guide.

Enter one complete HTTP or HTTPS link, or a domain name.

How to use it

  1. Check a link or website

  2. In Email, paste the message text; in Link, its address. Press Check and review the signals and actual domain. It does not open links or authenticate senders.

  3. Read the available fields alongside their limitations. An empty result does not prove safety or identify a person.

Synthetic example

Note

Invented example, not a real lookup. Do not call or open its links.

Synthetic example
https://[email protected]/notice

Interpret the result

Text before @ can hide the actual domain shown below.

Uses HTTP, without HTTPS encryption.

An internationalized domain needs careful review: some characters can look alike.

Uses a numeric IP address instead of a domain name.

No obvious warning signs found

Limitations

Warning

Checked on this device. Your text is not uploaded or saved.

Checks wording and visible links only. The sender, attachments and website contents are not verified.

Troubleshooting

Enter one complete HTTP or HTTPS link, or a domain name.

Use with the API

Warning

Needs an API key and credits. Each completed call costs 1 credit, even when there is no data. An active Pro account includes 20 credits per UTC calendar month, shared by every API route and spent first; unused monthly credits do not roll over. Credits bought on your account page work without Pro and never expire.

Note

Errors are never charged: 401 invalid_api_key (missing or invalid key), 403 pro_required (no Pro credits and no purchased credits), 422 invalid input, 429 quota_exceeded (no credits left), rate_limit_exceeded or ai_busy (the AI of sms-check is at capacity), 503 tool_warming (the data is still being prepared) or tool or provider unavailable. After a 429 or 503, retry once the seconds in the Retry-After header have passed.

Static inspection of one URL: host in Unicode and ASCII, whether it is an official brand or government domain (and whose), structural link flags and rule-engine signals. No fetch, redirect following or reputation lookup.

Send the JSON body to the tool's own route, or to POST /v2/tools with the tool field added. Both routes return the same result.

Endpoint
POST https://api.nocall.io/v2/link-check
POST https://api.nocall.io/v2/tools  {"tool":"link-check","url":"http://192.168.1.1/login","country":"ES"}

Parameters

NameTypeRequiredDescription
urlstring (1–2000)YesURL to inspect. It is never fetched.
countrystring (enum, 55)No (default: "ES")Country whose SMS rule set is used.
bash
REQUEST_ID="$(uuidgen)" && [ -n "$REQUEST_ID" ] &&
curl --request POST 'https://api.nocall.io/v2/link-check' \
  --header "Authorization: Bearer $NOCALL_API_KEY" \
  --header 'Content-Type: application/json' \
  --header "Idempotency-Key: $REQUEST_ID" \
  --data '{"url":"http://192.168.1.1/login","country":"ES"}'

Example response (200)

This is the documented example from the API reference. Lookups use a fictional number, and aggregates and AI answers show the shape of the result, not live data.

JSON
{
  "data": {
    "tool": "link-check",
    "result": {
      "host": "192.168.1.1",
      "hostAscii": "192.168.1.1",
      "official": false,
      "brand": null,
      "hosts": [
        "192.168.1.1"
      ],
      "linkFlags": [
        "http",
        "ipAddress"
      ],
      "signals": [
        "suspicious_domain"
      ],
      "attention": true
    }
  },
  "meta": {
    "requestId": "req_example",
    "unitsCharged": 1,
    "usage": {
      "periodStart": "2026-10-01",
      "unitLimit": 20,
      "unitsUsed": 3,
      "unitsRemaining": 17
    }
  }
}

Result fields (data.result)

FieldTypeDescription
hoststringHost name of the URL, in Unicode form.
hostAsciistringHost name of the URL, in ASCII (punycode) form.
officialbooleanWhether the host is an official brand or government domain.
brandstring | nullWhose official domain the host is (a brand or a government body), or null.
hostsarray<string>Host names found in the text.
linkFlagsarray<"http" | "userinfo" | "internationalHost" | "ipAddress" | "nonStandardPort">Structural warnings about the link: http, userinfo, international host, IP address or non-standard port.
signalsarray<string (enum, 10)>Rule signals that matched.
attentionbooleanWhether the content deserves a closer look.