Line valid number check list: 5-step practical guide to verify whether your Line account is available

When doing Line community operations, private message marketing, or customer acquisition in Southeast Asia, one of the most troublesome problems is spending time importing a large number of numbers, only to find that most of them have not opened Line, or have turned into zombie accounts. Not to mention wasting money and energy, the account may also be flagged due to frequent invalid sending. This article will provide a complete Line valid number check list, from number sorting, platform detection to result interpretation, 5-step operation to help you accurately screen out the truly available Line accounts.

What is a valid Line number? Why does overseas marketing need to check Line validity?

Line valid number refers to a mobile phone number that has successfully registered a Line account and can receive messages (including verification codes, notifications, and chat messages) normally. In contrast, there are unregistered numbers (never opened a Line), canceled numbers or accounts that have been inactive for a long time.

In Southeast Asia (especially Vietnam and Thailand) and the global Chinese market, Line is an important reach channel. However, if you directly purchase a number segment or a randomly generated number, the activation rate may be as low as 10%~20%. Using unverified numbers to send mass messages will not only have a very low reach rate, but may also trigger Line’s risk control mechanism, resulting in the sending account being banned. Therefore, verifying the validity of Line numbers in batches before formal marketing is the first step to reduce risks and increase ROI.

Step 1: Organize and import the list of numbers to be checked

Number source and format requirements

Your original number can come from multiple sources:

• Manual collection: Mobile phone numbers obtained from customer registration forms and offline activities
• CSV/TXT import: Existing contact list can be uploaded directly through the KK-DATA console
• Global number segment generation: Use KK-DATA’s number generator to generate candidate number segments by country/region and operator (generation is free, screened numbers are charged on a per-item basis)

Format Suggestion: Use the pure numeric form of “country code + number”, such as Vietnam number 84912345678 (remove the + sign and spaces). KK-DATA will automatically identify the area code, so there is no need to manually add the dialing prefix for international users.

Data deduplication and cleaning: avoid repeated deductions

Each number screening task will be deducted according to the number of detections. Repeated detection of the same number is equivalent to wasting money. KK-DATA’s data deduplication warehouse can compare detected numbers across tasks and automatically eliminate duplicates.

Duplication Cleaning Checklist:

• When merging multiple batch numbers, the duplicate warehouse will automatically identify
• Manually clean spaces, brackets, dashes and other special characters in numbers
• Confirm whether the country code is correct (for example, Vietnam is +84, Thailand +66, Taiwan +886)
• Unify the numbers into E.164 format (no prefix + sign) before importing

After completing the cleaning, proceed to the next step to create a screen number task.

Step 2: Use the Line screening function for validity testing

Submit screening task: select Line and detection type

1. Log in to KK-DATA Console
2. Click “New Screening Task” and select the “Line” platform
3. Check the required detection type:
   • Activation detection (required): Determine whether the number has registered a Line account
   • Activity Detection (optional): Determine whether the account has been active in the past 30 days (such as sending and receiving messages, logging in)
   • Gender Identification (optional): Return male/female/unknown for targeted customer acquisition
4. Upload a list of numbers or select from generated records
5. Confirm the estimated cost (the system will display the amount expected to be deducted for this task, see the real-time price on the console for details)
6. Submit the task and wait for completion (supports background operation and can set completion notification)

Interpret the test results: field description (Line enabled, Line valid, Line gender, uid)

After the detection is completed, export the CSV file and you will see the following main fields (subject to the actual export of KK-DATA):

Field	Meaning	Typical values
phone	Number to be tested	84912345678
line_open	Whether to register Line	1=Registered, 0=Not registered
line_active	Whether active in the past 30 days	1=active, 0=inactive or no data
line_gender	Gender prediction	male / female / unknown
uid	Line user’s unique ID (can be used for subsequent precise contact)	Number or mixed string

Export filtered valid numbers in batches

On the task results page, you can filter by conditions:

• Export all numbers with line_open=1 (only registered users)
• Export numbers with line_open=1 and line_active=1 (high-quality active users)
• Export the number of line_gender=male (targeted to male users)

The exported format supports CSV and TXT. After downloading, it can be directly used for Line mass sending or imported into CRM.

How to determine the activity and gender data of a Line number? (Advanced usage)

• Activated vs. Active: Activated means that the number is indeed registered with Line, but may not be used for a long time (for example, it has not been logged in for half a year).活跃表示近30天内有正常使用行为，是更优质的营销对象。 If the budget is limited, give priority to using the “open + active” double filtering.
• Gender Targeting: If you are promoting men’s products (games, sports equipment) or women’s products (beauty, maternal and infant products), you can use the line_gender field to filter out the target gender and improve the conversion rate.
• Active window customization: In the KK-DATA task configuration, you can select active determination windows such as “near 7 days”, “near 30 days”, and “near 90 days”. For activities with high timeliness requirements (such as limited-time promotions), it is recommended to use a 7-day window; for brand-building messages, a 30-day window is more appropriate.

Common misunderstanding: Why can’t you just buy a number segment without verifying it?

Many sellers provide “Line number segments” or “Vietnam Line account lists”, claiming that the numbers are “valid”. But actual testing found:

• Extremely low activation rate: After actual testing of randomly generated or batch-purchased number segments, the activation rate is often less than 10% (for example, only 80 of 1,000 number segments have registered Line).
• Poor number effectiveness: Registered numbers may also be recycled by Line or abandoned by users. Without regular verification, they will become an invalid list.
• Triggering account ban: If you send messages to a large number of unregistered numbers, Line will judge it as harassment, which will range from restricting the sending to permanently banning the account.

Correct approach: First use the number generator to obtain the candidate list, then conduct Line validity testing through KK-DATA, and finally use only line_open=1 numbers for marketing. The generation is free, and the screen numbers are charged on a per-item basis. You pay for what you use.

4 Best Practices: Improve Line Screening Efficiency and Accuracy

1. 分批检测：单次任务建议不超过100万条号码。 If the number is very large (such as more than 5 million), split it into multiple tasks and submit them in parallel to avoid long processing time due to excessive data volume.
2. Make good use of data deduplication warehouse: After each detection, KK-DATA will automatically record the detected number. The next time you import a new list, the deduplication warehouse will skip duplicate items to save balance.
3. Turn on task completion notification: Bind Telegram on the console and you will receive a notification immediately after the task is completed. Even if you are not in front of the computer, you can download the results in time to speed up the marketing pace.
4. Periodic rescreening: The active status of the number will change over time. It is recommended to recheck the activity of old numbers every 3 months and eliminate the expired ones to keep the list fresh.

FAQ

Q: What is the difference between Line valid number and Line active number?
答： “有效号码”指号码已注册Line账号（line_open=1），但不保证近期有使用行为。 “Active number” refers to an account that has logged in or sent and received messages in the last 30 days (or a custom window) (line_active=1). Active numbers are higher quality marketing objects than valid numbers.

Q: Is Line gender detection accurate? Can it be used as a basis for placement?
Answer: Line gender is inferred based on account behavioral characteristics (such as avatar, nickname wording, interaction objects), and the accuracy is high but not 100%. It is recommended to be used for “high probability orientation” rather than as the only voucher. In actual delivery, A/B testing can be combined to verify the effect.

Q: How many numbers can be detected at most at one time?
Answer: KK-DATA supports up to about 1 million numbers in a single task. If this amount is exceeded, it is recommended to submit in batches. Billing is deducted based on the actual number of tests. For specific unit prices** please see the real-time price on the console**.

Q: Is number generation free? Can it be used directly for screen numbers after generation?
Answer: The global number generation function is completely free and supports randomly generated or customized number segments in 240+ countries/regions. The generated numbers can be used as input to the screening task. Fees will only be deducted on a per-item basis during the screening (testing) step.

Q: If the Line activation rate is found to be very low after testing, can the generated number be used?
Answer: Even if the activation rate is only 10%, the generated numbers are still an effective “candidate pool”, and the 10% accurate users can be extracted after screening. Compared with purchasing unverified lists directly, generating + screening numbers yourself is cheaper and the data is more controllable.

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Through the above 5 steps, you can efficiently build your own Line valid number list, avoid invalid investment, and improve customer acquisition efficiency. Start your first screening task now!

👉 Log in to the console to start screening numbers Two-way contact customer service https://t.me/kkdata_robot For more functions and billing instructions, please refer to Usage Document and Official Website Billing Page.