How to Use LINE Number Checker for Bulk List Checks
LINE is the messenger where brands run official accounts, and that changes what a number check is for. On most apps, on-platform means reachable. On...
Ethan works on phone-number normalization, E.164 formatting, country-code rules, carrier metadata, and line-type detection. His editorial work turns verification signals into practical workflows for CRM cleaning, SMS preparation, lead review, and bulk data operations.
View full author profile →LINE is the messenger where brands run official accounts, and that changes what a number check is for. On most apps, on-platform means reachable. On LINE, on-LINE is the ticket into official-account messaging, and the check is about counting tickets, not just cleaning a list. LINE Number Checker is the ZelNum page that supports this job: LINE Number Checker.
Quick answer
Prepare a CSV with one number per row, a record ID, and the market and segment fields filled. Run the check, read the on-LINE status per row, and route by what the row is for: subscription growth wants on-LINE rows invited to the official account, marketing wants reachable rows, review wants to know which rows moved. The market split matters because LINE’s reach is not uniform anywhere.
The ticket to the official account
On LINE, a person who uses the app is not automatically a customer of your official account. But they are reachable through it, and that reach is the precondition for LINE-based brand messaging. On-LINE is the ticket; the official-account subscription is the goal.
So the check answers two questions in one pass:
- Is this number on LINE? (the ticket)
- What is the market and segment of this row? (what the ticket is worth)
Step 1: Prepare the file with market and segment
Keep the market column (Japan, Taiwan, Thailand, Indonesia, and so on) and, if you have it, the segment column (trial, paying, support, and so on). These two fields decide how the on-LINE signal is read. Drop them and the file becomes numbers with no campaign shape.
Step 2: Run the check
The export returns a status per row: on LINE, valid but not on LINE, invalid, or unknown. Read them as routing signals:
| Status | Typical action |
|---|---|
| On LINE | The ticket exists. Route to the OA invitation or the LINE workflow. |
| Valid, not on LINE | The number is good, the channel is wrong. Route to SMS. |
| Invalid | Repair if obvious, otherwise suppress. |
| Unknown | Hold for retry. |
Step 3: Read by market, then by segment
LINE’s reach is a map: Japan is the core, Taiwan and Thailand are strong, Indonesia is real but thinner. Within a market, the segment tells you what the ticket is worth. A paying customer on LINE in Japan is the highest-value row in the file; a trial user in a thin market is a different decision entirely.
Say the file holds 11,600 numbers across four markets. The on-LINE share comes back 86% for Japan, 79% for Taiwan, 63% for Thailand, and 38% for Indonesia. (These figures are illustrative, not a product performance claim.) Those are four campaign shapes, not one percentage.
Step 4: Route and schedule
- On-LINE rows in strong markets go to the OA invitation flow.
- Valid-but-not-on-LINE rows go to SMS.
- Re-check quarterly, and before any big OA campaign, because on-LINE status drifts as accounts go dormant.
Mistakes to avoid
- Treating “on LINE” as “subscribed to the official account.” The ticket is not the goal. The invitation is the follow-up, and a ticket without a follow-up is a wasted check.
- Reading one percentage for every market. A flat on-LINE number hides the market split that decides the campaign.
- Dropping the segment column. Trial rows and paying rows are different jobs, and the segment field is what tells them apart.
FAQ
What is the difference between on LINE and subscribed to the official account?
On LINE means the number is tied to a LINE account. Subscribed means it is following your official account. The check counts tickets; the invitation flow converts tickets into subscriptions.
Why does the market column matter?
Because LINE’s reach is concentrated. An on-LINE share of 86% in Japan and 38% in Indonesia are different realities, and the market field is what lets you tell them apart.
What should I do with valid-but-not-on-LINE rows?
Route them to SMS or another channel. The number is good; the LINE channel is wrong for it.
How often should I re-check?
Quarterly is a reasonable baseline, plus a re-check before any big OA campaign.
Can on-LINE status change?
Yes. Accounts go dormant and numbers get recycled, so a checked row is only true as of its timestamp.
Related ZelNum pages
- LINE Number Checker Use Cases for how different teams read the same export.
- Bulk LINE Number Checker: CSV Upload and Result Export Guide for the file format details.