---
title: "Phone Numbering-Plan Validation API"
url: "https://lookvalid.com/products/phone.md"
canonical_url: "https://lookvalid.com/products/phone"
last_updated: "2026-10-22"
type: "product"
summary: "Checks a phone number against its country's numbering plan and returns E.164, national and international formats."
related: ["https://lookvalid.com/pricing.md", "https://lookvalid.com/docs/api/phone.md"]
---

# Phone Numbering-Plan Validation API

Checks a phone number against its country's numbering plan and returns E.164, national and international formats.

Checks a phone number against its country's numbering plan and returns E.164, national and international formats, the country and the number type the plan assigns (mobile, fixed line, toll free, VoIP and others). Uses open libphonenumber metadata only: it does not query carriers, so it cannot tell whether a number is active, ported or reachable.

## Facts

- Endpoint: `POST https://YOUR_API_HOST/v1/phone`
- Price: 1 credit per valid number
- Charged: Only when a lookup finds something
- Cache: repeating the same lookup within 7 days is free

## Example request

```sh
curl -X POST https://YOUR_API_HOST/v1/phone \
  -H "Authorization: Bearer $LOOKVALID_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"phone":"+14155550132"}'
```

## Response

The `data` object has 14 named fields. Every response also lists the sources behind the result, the credits charged and whether it was served from your cache.

| Field | Type | Description |
| --- | --- | --- |
| `valid` | true | Always true: a number the numbering plan rejects is a free not_found |
| `possible` | boolean |  |
| `e164` | string |  |
| `national_format` | string |  |
| `international_format` | string |  |
| `country_calling_code` | string |  |
| `country` | string or null |  |
| `number_type` | "mobile" | "fixed_line" | "fixed_line_or_mobile" | "voip" | "toll_free" | "premium_rate" | "shared_cost" | "personal_number" | "pager" | "uan" | "unknown" |  |
| `line_type_source` | "numbering-plan" |  |
| `carrier` | null |  |
| `area_code` | string or null |  |
| `area_code_region` | object or null |  |
| `extension` | string or null |  |
| `notes` | string |  |

## Priced in credits

| Case | Charge |
| --- | --- |
| Found | 1 credit |
| Nothing found | 0 credits |
| Repeat inside 7 days | 0 credits |
| Errors and invalid requests | 0 credits |

## Questions

### How much does Phone Numbering-Plan Validation cost?

1 credit per valid number. Credits come out of the one balance shared by every LookValid product.

### Am I charged when nothing is found?

No. When the lookup runs and finds nothing, it returns found: false and costs 0 credits. An error costs nothing either.

### How long are results cached?

For 7 days, per account. Repeating the same lookup inside that window returns cache_hit: true and costs 0 credits.

### Which API key do I use?

The same key as every other product. Send it as a Bearer token in the Authorization header. Email hello@lookvalid.com and we set up your account and send the key.

## Related products

- [Country Calling Codes](https://lookvalid.com/products/country-code.md): Looks up a country by calling code (+44), ISO region (GB) or English country name and returns the calling code, every region that shares it, national number lengths, trunk and international dialing prefixes, example numbers and the leading digits of mobile and fixed-line numbers where the numbering plan defines them.
- [Email Domain Check](https://lookvalid.com/products/email-domain-check.md): Checks the domain behind an email address: MX records, SPF and DMARC policies, and whether the address uses a disposable domain, a free mailbox provider or a role mailbox such as info@ or support@.
- [IP Intelligence](https://lookvalid.com/products/ip.md): Location and network details for an IPv4 or IPv6 address (country, region, city, time zone, ASN and network owner) with risk flags from open lists such as Tor exit nodes and cloud provider ranges.

Full request and response fields: [Phone Numbering-Plan Validation reference](https://lookvalid.com/docs/api/phone.md).

## Related

- [Plans, trial and credit pricing](https://lookvalid.com/pricing.md)
- [Phone Numbering-Plan Validation reference](https://lookvalid.com/docs/api/phone.md)