> For the complete documentation index, see [llms.txt](https://wiki.mobivatebulksms.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://wiki.mobivatebulksms.com/archived-integrations/synchronous-number-verification.md).

# Synchronous Number Verification

Learn how to use our Synchronous number verification system

To verify if the number is valid (active on any network), you can request a Home Location Register (HLR) lookup.

```http
HTTP GET: https://hlr.mobivatebulksms.com/?lookup={msisdn,msisdn,...}&username={your username}&password={your password}
```

On success, we will return **JSON**:

```json
{
  results: [
    {
      to: "4474*******",
      mccMnc: "23430",
      imsi: "23430",
      originalNetwork: {
        networkName: "T-Mobile UK (Everything Everywhere Limited)",
        networkPrefix: "74326",
        countryName: "United Kingdom",
        countryPrefix: "44"
      },
      ported: false,
      status: {
        groupId: 3,
        groupName: "DELIVERED",
        id: 5,
        name: "DELIVERED_TO_HANDSET",
        description: "Message delivered to handset"
      },
      error: {
        groupId: 0,
        groupName: "OK",
        id: 0,
        name: "NO_ERROR",
        description: "No Error",
        permanent: false
      }
    },
    { ... },
  ]
}
```