> Enrich.chat gives AI agents verified work emails and mobiles. To use it from an agent, read https://enrich.chat/agents.md . This is the Markdown version of https://enrich.chat/tools/phone-number-validator/

> **Note for agents:** this tool is a web form that people use in a browser, so you cannot submit it. Use the Enrich.chat API instead, as described in https://enrich.chat/agents.md .

# Free phone number validator and line type lookup

Enter a phone number to see if it is valid, whether it is a mobile, landline or VoIP line, and which country it is in.

By Enrich.chat Editorial. Updated October 15, 2026.

## What you get

- Valid or invalid, with the number in E.164 format
- Line type: mobile, landline, VoIP or toll-free
- The country and the E.164 number

**Short answer:** A phone number validator checks a number against its country's numbering plan, rewrites it in E.164 format (a plus sign and at most 15 digits, per the [ITU-T E.164](https://www.itu.int/rec/T-REC-E.164/en) standard) and tells you if it is mobile, landline, VoIP or toll-free. A valid format does not prove the number is in use, as [Google's libphonenumber](https://github.com/google/libphonenumber/blob/master/java/libphonenumber/src/com/google/i18n/phonenumbers/PhoneNumberUtil.java) notes. Only a live network check shows the line works today.

## Key takeaways

- E.164 numbers start with + and hold at most 15 digits. No country code starts with 0.
- In the US you cannot tell a mobile from a landline by its digits, so line type needs carrier data.
- A live line check shows a mobile works. It does not show who owns it.
- Autodialed or prerecorded calls and texts to a US mobile need prior consent under FCC rules.

## Three steps, a few seconds

1. **Enter the number.** Type it in any format and pick the country, or start with + and the country code.
2. **Run the check.** The validator checks the format, the country and the line type.
3. **Read the result.** See valid or invalid, the E.164 number, the line type and the country.

## How do you check if a phone number is valid?

You check a phone number in three layers: its format, the numbering plan, and the live network. Each layer answers a different question, and only the last one tells you the line works today.

The format check runs offline. [Google's libphonenumber](https://github.com/google/libphonenumber), the open-source library behind many validators, has two tests. The "possible" test looks only at the length. The "valid" test uses the length and the prefix rules for the country. Even a valid result has limits. The library's own code says the test [doesn't verify the number is actually in use](https://github.com/google/libphonenumber/blob/master/java/libphonenumber/src/com/google/i18n/phonenumbers/PhoneNumberUtil.java), because you can't tell that from the digits.

| Layer | What it tells you | What it misses |
| --- | --- | --- |
| Format (length and prefix rules) | Typos, missing digits, a wrong country code | Whether anyone has the number |
| Numbering plan (prefix data) | Likely line type, first carrier, country | Ported numbers and the current carrier |
| Live network (HLR or carrier query) | Live line, current network, porting | Who owns the line |

The validator at the top of this page covers the first two layers. You get valid or invalid, the number in E.164 format, the line type and the country. It cannot tell you whether the line is live, which takes a network check. Each check uses 1 of your 10 free lookups.

## What is E.164 format?

E.164 is the international phone number format defined in the [ITU-T E.164 recommendation](https://www.itu.int/rec/T-REC-E.164/en). A number in E.164 format starts with a plus sign, uses only digits, and holds [at most 15 digits](https://www.twilio.com/docs/glossary/what-e164).

Every E.164 number has three parts after the plus sign. The country code is 1 to 3 digits, and [no country code starts with 0](https://www.twilio.com/docs/glossary/what-e164). Next comes the national destination code, which in the US is the area code. The subscriber number comes last.

**Figure 1: Anatomy of an E.164 phone number.** The number +1 415 555 0142 split into four parts: the plus sign, country code 1, area code 415 and subscriber number 555 0142. Stored in E.164 it reads +14155550142, which is 11 of the 15 digits allowed.

*The parts of an E.164 number, using a sample US number. Sources: [ITU-T E.164](https://www.itu.int/rec/T-REC-E.164/en) and [Twilio's E.164 summary](https://www.twilio.com/docs/glossary/what-e164).*

To convert a local number, add the country code and drop the local prefix you dial at home. Google's libphonenumber gives the example of +41 (0) 78 927 2696, which it [parses into country code 41 and national number 789272696](https://github.com/google/libphonenumber/blob/master/java/libphonenumber/src/com/google/i18n/phonenumbers/PhoneNumberUtil.java). The (0) goes away. Store every number this way in your CRM, and each number has exactly one spelling, so duplicates are easy to find.

## Is this phone number a mobile, landline or VoIP line?

A line-type lookup tells you whether a number is mobile, landline, VoIP or toll-free. The line type decides whether you can text the number and which calling rules apply.

In the US you can't tell from the digits alone. Google's libphonenumber has a special FIXED_LINE_OR_MOBILE type because, in regions like the US, it is [impossible to tell fixed-line and mobile numbers apart](https://github.com/google/libphonenumber/blob/master/java/libphonenumber/src/com/google/i18n/phonenumbers/PhoneNumberUtil.java) by the number itself. Porting adds to the problem. Under [FCC rules](https://www.fcc.gov/consumers/guides/porting-keeping-your-phone-number-when-you-change-providers), you can keep your number when you switch between wireline, IP and wireless providers in the same area. A number that began as a landline can be a mobile today, so a reliable line type needs carrier data.

| Line type | Can you text it? | What it is |
| --- | --- | --- |
| Mobile | Yes, with consent for autodialed texts | A cellular line on a carrier network |
| Landline | Generally not | A fixed line at a home or office |
| Fixed VoIP | Depends on the provider | A virtual number tied to a physical device |
| Non-fixed VoIP | Depends on the provider | A virtual number you get online with no device, such as Google Voice |
| Toll-free | Only if it is text enabled | A number with an 800, 888, 877, 866, 855, 844 or 833 code |

[Twilio's line-type definitions](https://www.twilio.com/docs/lookup/v2-api/line-type-intelligence) say a landline generally can't receive SMS, while a mobile generally can. They split VoIP in two: fixed VoIP tied to a physical device, such as service from Comcast or Vonage, and non-fixed VoIP you get online with no device, such as Google Voice. The [FCC lists seven toll-free codes](https://www.fcc.gov/consumers/guides/what-toll-free-number-and-how-does-it-work) and says toll-free numbers can take texts only when they are text enabled.

## How does a carrier lookup work?

A carrier lookup finds the network operator for a phone number. One kind returns the carrier that was first given the number range. The other returns the carrier that serves the number today.

The first kind is a table lookup. It is fast and cheap, but it goes stale when a number is ported. Google's libphonenumber is open about this. In regions with mobile number portability, its carrier data [returns the original carrier](https://github.com/google/libphonenumber/blob/master/FAQ.md), and its README says [it does not provide the current carrier](https://github.com/google/libphonenumber) of a number.

The second kind checks live routing data. In the US, the record of which carrier serves each ported number sits in the [Number Portability Administration Center (NPAC)](https://iconectiv.com/NPAC), which iconectiv runs. Access is limited to service providers and providers of telecom-related services. For mobiles, the other route to the current network is an HLR lookup.

Ports happen fast. [FCC rules require simple ports in one business day](https://www.fcc.gov/consumers/guides/porting-keeping-your-phone-number-when-you-change-providers), and a move between wireless carriers can take only a few hours. A carrier result from last month may already be wrong.

## What is an HLR lookup, and what does a live line check tell you?

An HLR lookup asks a mobile network's Home Location Register whether a number is assigned and reachable. The 3GPP standard defines the HLR as [the register a mobile subscriber is assigned to for record purposes](https://www.etsi.org/deliver/etsi_ts/123000_123099/123002/17.00.00_60/ts_123002v170000p.pdf). On 4G networks, the Home Subscriber Server does the same job.

The lookup travels over SS7, the signalling network carriers use to talk to each other. [HLR Lookup, a vendor, explains](https://www.hlrlookup.com/how-do-hlr-lookups-work) that it sends an SRI-for-SM request, the query used to route a text message. The network answers with the number's status, its current network and whether it was ported.

**Figure 2: How an HLR lookup checks a live line.** A live-line check sends an SRI-for-SM query over the SS7 network to the home network's HLR, which holds the subscriber record. The HLR answers active, absent or dead, plus the current network and whether the number was ported. The answer describes the number, not the person.

*What an HLR lookup asks and the three statuses it can return. Sources: [3GPP TS 23.002](https://www.etsi.org/deliver/etsi_ts/123000_123099/123002/17.00.00_60/ts_123002v170000p.pdf) and [HLR Lookup](https://www.hlrlookup.com/how-do-hlr-lookups-work).*

A live line check is useful, but narrow. It shows the number works. It does not show who holds it: HLR Lookup states that a lookup describes a telephone number, [not a telephone user](https://www.hlrlookup.com/how-do-hlr-lookups-work). A live mobile can belong to a new owner after the old one gave it up. The HLR is a mobile network register, so this check is built for mobiles, not landlines.

Enrich.chat does not run a network check. When your [AI agent](https://enrich.chat/agents/) asks the [LinkedIn to email and mobile API](https://enrich.chat/api/linkedin-to-contact/) for a person's mobile, the response marks the line as `mobile` or `unknown`, which is the number's type, not proof that it works today. A mobile found uses 250 credits and a lookup that finds none uses 0, as the [pricing page](https://enrich.chat/pricing/) shows. To find a mobile for a specific person, try the [LinkedIn email and phone finder](https://enrich.chat/tools/linkedin-email-finder/), or read [how to get phone numbers from LinkedIn](https://enrich.chat/blog/find-phone-number-from-linkedin/). For office lines, see [how direct dials differ from mobiles](https://enrich.chat/blog/direct-dials/).

```text
Use www.enrich.chat to find the mobile number for linkedin.com/in/jane-doe and tell me its line type
```

## Can you call or text a mobile number after you validate it?

Validation tells you a mobile can be reached. It does not give you permission to reach it. In the US, the Telephone Consumer Protection Act (TCPA) and the FCC's rules set consent rules for calls and texts to mobiles, and the [FCC says they apply](https://www.fcc.gov/consumers/guides/stop-unwanted-robocalls-and-texts) even if the number is not on the Do Not Call Registry.

- Autodialed or prerecorded calls and texts to a mobile need the owner's [prior oral or written consent](https://www.fcc.gov/consumers/guides/stop-unwanted-robocalls-and-texts).
- Prerecorded telemarketing calls need prior written consent, which can be a website form or a keypress.
- Commercial texts need written consent. Informational texts can rely on oral consent.
- People can opt out of any robocall or robotext at any time, in any reasonable way.
- Each violation can cost [$500 in damages, and a court can triple that](https://www.law.cornell.edu/uscode/text/47/227) if the violation was willful or knowing.

The Supreme Court narrowed what counts as an autodialer in [Facebook v. Duguid (2021)](https://www.supremecourt.gov/opinions/20pdf/19-511_p86b.pdf). The equipment must use a random or sequential number generator to store or produce numbers. That ruling is about dialing equipment only. The [statute's rules on artificial or prerecorded voice calls](https://www.law.cornell.edu/uscode/text/47/227) to mobiles still apply.

Consent also goes stale when a number changes hands. The FCC's [Reassigned Numbers Database](https://www.fcc.gov/reassigned-numbers-database) lets you check whether a number may have been reassigned since you got consent. It opened to paid subscribers on November 1, 2021. If the database wrongly says a number was not reassigned, the caller may be protected from TCPA liability.

**Figure 3: Should you call or text this number?** A decision tree with four checks in order: is the format valid, is it a mobile line, is the line live, and do you have consent. A no at any step leads to a stop or a fix. Four yes answers mean the number is safe to call or text, with a check of the FCC Reassigned Numbers Database when consent is old.

*A pre-dial check for US mobile numbers. It is a summary, not legal advice. Sources: [FCC robocall and robotext rules](https://www.fcc.gov/consumers/guides/stop-unwanted-robocalls-and-texts) and the [FCC Reassigned Numbers Database](https://www.fcc.gov/reassigned-numbers-database).*

You are responsible for TCPA compliance when you call or text numbers from any source, including Enrich.chat. Anyone can remove their own data at the [Enrich.chat opt-out page](https://enrich.chat/opt-out/). If you build outreach into an agent, our guide to [AI lead generation](https://enrich.chat/blog/ai-lead-generation/) covers the rest of the workflow.

## Frequently asked questions

### Is this phone number validator free?

Yes. The validator is free and needs no signup. Every visitor gets 10 free lookups, shared across the Enrich.chat website tools, and each phone check uses one. If you need more, your AI agent can call the Enrich.chat API with 10 free lookups a day, then monthly plans from $29 for 100,000 credits, where credits are spent only on matches. See [Enrich.chat pricing](https://enrich.chat/pricing/) for every plan.

### Can a phone number validator tell me who owns a number?

No. A phone number validator describes the number, not the person. Format checks, carrier lookups and HLR lookups show whether a number is valid, which network serves it and whether the line is live. [HLR Lookup notes](https://www.hlrlookup.com/how-do-hlr-lookups-work) that a lookup gives information about a telephone number, not a telephone user. A live line can also belong to someone new after the old owner gave the number up.

### How can I tell if a number is Google Voice or another VoIP line?

Run a line-type lookup that uses carrier data. In the US, Google's libphonenumber cannot even separate mobile and fixed-line numbers from the digits, so a prefix table will not spot VoIP reliably. [Twilio's line-type definitions](https://www.twilio.com/docs/lookup/v2-api/line-type-intelligence) class Google Voice as non-fixed VoIP, a number you can get online with no physical device, and keep it apart from fixed VoIP tied to a physical device.

### What is the difference between a valid and a possible phone number?

A possible phone number has the right length for its country. A valid phone number also matches the country's prefix rules. Google's [libphonenumber](https://github.com/google/libphonenumber) runs both tests: isPossibleNumber checks length only, and isValidNumber checks length and prefix. Neither test shows that the number is in service. For that you need a live check against the mobile network.

### Why does a valid phone number say it is not in service?

A valid number only matches the numbering plan. It may not be assigned to anyone. [Google's libphonenumber FAQ](https://github.com/google/libphonenumber/blob/master/FAQ.md) says not to rely on validity to tell whether a number is assigned and reachable. A live HLR lookup can report such a number as dead, which [HLR Lookup defines](https://www.hlrlookup.com/how-do-hlr-lookups-work) as valid but not currently assigned to a subscriber.

### How do I validate phone numbers in bulk?

For format alone, run Google's open-source [libphonenumber](https://github.com/google/libphonenumber) in your own code. It is free and needs no network calls. For line type and live status you need a lookup service that queries carrier data. If you need working mobiles for a list of people, ask your AI agent to use [Enrich.chat](https://enrich.chat/agents/): each mobile comes with its line type, and a mobile found uses 250 credits on a plan, with 0 credits when none is found.

## Sources

1. [Recommendation E.164: The international public telecommunication numbering plan](https://www.itu.int/rec/T-REC-E.164/en)
2. [What is E.164?](https://www.twilio.com/docs/glossary/what-e164)
3. [libphonenumber README](https://github.com/google/libphonenumber)
4. [libphonenumber FAQ](https://github.com/google/libphonenumber/blob/master/FAQ.md)
5. [PhoneNumberUtil.java (isValidNumber and PhoneNumberType)](https://github.com/google/libphonenumber/blob/master/java/libphonenumber/src/com/google/i18n/phonenumbers/PhoneNumberUtil.java)
6. [Line Type Intelligence](https://www.twilio.com/docs/lookup/v2-api/line-type-intelligence)
7. [Porting: Keeping Your Phone Number When You Change Providers](https://www.fcc.gov/consumers/guides/porting-keeping-your-phone-number-when-you-change-providers)
8. [What Is a Toll-Free Number and How Does It Work?](https://www.fcc.gov/consumers/guides/what-toll-free-number-and-how-does-it-work)
9. [Number Portability Administration Center (NPAC)](https://iconectiv.com/NPAC)
10. [3GPP TS 23.002 Network architecture (ETSI TS 123 002 V17.0.0)](https://www.etsi.org/deliver/etsi_ts/123000_123099/123002/17.00.00_60/ts_123002v170000p.pdf)
11. [How do HLR Lookups work?](https://www.hlrlookup.com/how-do-hlr-lookups-work)
12. [Stop Unwanted Robocalls and Texts](https://www.fcc.gov/consumers/guides/stop-unwanted-robocalls-and-texts)
13. [47 U.S. Code § 227: Restrictions on use of telephone equipment](https://www.law.cornell.edu/uscode/text/47/227)
14. [Facebook, Inc. v. Duguid, No. 19-511](https://www.supremecourt.gov/opinions/20pdf/19-511_p86b.pdf)
15. [Reassigned Numbers Database](https://www.fcc.gov/reassigned-numbers-database)

## Need a working mobile for a person?

Your AI agent can find a person's mobile through the Enrich.chat API. Each one comes with its line type. 10 free lookups a day, then monthly plans from $29, where a mobile found uses 250 credits.

```bash
curl "https://enrich.chat/v1/mobile?linkedin_url=linkedin.com/in/jane-doe"
```

## Try this prompt

Get a mobile from your agent

```text
Use www.enrich.chat to find the mobile number for linkedin.com/in/jane-doe and tell me its line type
```

## Related

- [LinkedIn email and phone finder](https://enrich.chat/tools/linkedin-email-finder/)
- [How to get phone numbers from LinkedIn](https://enrich.chat/blog/find-phone-number-from-linkedin/)
- [Direct dials explained](https://enrich.chat/blog/direct-dials/)