What’s the difference between LOOKUP and HLR?

Numberyo offers two main verification services: LOOKUP and HLR. While they both help you validate phone numbers, they serve different purposes and operate at different levels.

Here is a breakdown of the differences between them:

1. LOOKUP - Format and Line Type Validation

LOOKUP is used to analyze the structure and metadata of a phone number. It checks:

• If the number is correctly formatted

• The country and region it belongs to

• The line type (mobile, landline, VoIP, etc.)

• The carrier information (when available)

Use case:
LOOKUP is useful when you want to quickly clean or validate a list of numbers before storing them in your database or using them in a campaign.

Pros:

• Fast and lightweight

• Ideal for bulk processing

• Works with numbers worldwide

• No access to the network is required

2. HLR - Network Reachability Check

HLR stands for Home Location Register. This check connects with the mobile network to determine if a phone number is active and reachable.

It verifies:

• If the number is currently registered on the network

• If the number exists and is reachable

• The current carrier (including number portability)

• Whether the number is roaming

Use case:
HLR is ideal before sending SMS messages, OTPs, or important notifications. It helps avoid sending messages to numbers that are no longer in service.

Pros:

• Accurate network-level validation

• Helps reduce SMS delivery failures

• Avoids sending to invalid or inactive numbers

• Saves messaging costs

Which one should you use?

• Use LOOKUP to clean and validate phone numbers before storing or segmenting them.

• Use HLR when you need to ensure that a number is active and reachable before sending a message.

In many cases, businesses use both in combination: LOOKUP to clean the data, and HLR to check reachability before sending SMS.