CheckNumber.AI 
Zalo Checker
zalo $2 per 10,000 checks
- Core data available
- number, activated
- Best for
- Vietnam audience sizing and list cleaning
No-code CSV REST API Exportable results
Verify Zalo Account Registration
Check whether a phone number is registered on Zalo, Vietnam's leading messaging app.
Zalo is Vietnam's dominant messaging and lifestyle super-app, used by businesses through Zalo Official Accounts for customer service, e-commerce, and even some government services — many Vietnamese consumers treat a Zalo account as more reachable than SMS or email. CheckNumber's Zalo checker confirms whether a phone number holds a registered Zalo account, so teams can size a Vietnam-focused audience or clean a contact list before running Zalo Official Account campaigns, without ever messaging the number.
E.164
Phone input
$2
Per 10,000 checks
CSV + API
Workflow
Submitted number +8490••••2233
Zalo status yes / no
Zalo Checker Zalo Days Checker Zalo Age & Gender Checker No account, number, or SIM required
Every check runs through official platform APIs on our own infrastructure. You never connect, bind, or use your own account, phone number, or SIM card — just upload your list or call the API and get results.
What CheckNumber detects for Zalo
Zalo account by phone
Confirms whether a phone number has a registered Zalo account (yes or no).
Vietnam audience sizing
Every number in a Zalo batch returns a registered or not-registered result for Vietnam audience sizing.
Passive, no contact
Reads the Zalo registration signal only — the account is never messaged, added, or notified.
What You Can Check
A focused Zalo registration check
Use the Zalo task when the required output is a row-level Zalo-registration signal mapped to each submitted E.164 phone number.
| Zalo product | Task type | Input | Core data available | Best for | Current price |
|---|---|---|---|---|---|
| Zalo Checker API documentation | zalo | Phone numbers in E.164 format | number, activated | Vietnam audience sizing and list cleaning | $2 per 10,000 checks |
Core Zalo data
What the Zalo task returns
The result file maps one row to each submitted number with the fields below.
Registration
zalo - number
- The phone number supplied for the check, in E.164 format.
- activated
- Whether the number is registered on Zalo (yes or no).
The zalo field is a boolean registration signal only — it does not include Zalo display names, avatars, or Official Account interactions.
Run a Zalo batch in three steps
Use the no-code platform for uploaded lists or the REST API for recurring workflows.
- 1
Prepare E.164 numbers
Provide one international phone number per row with country code.
- 2
Create the zalo task
Upload the file or call the API with task_type set to zalo.
- 3
Export mapped rows
Download the completed file and match each result to its source number.
Common Use Case
Improve Zalo list quality before outreach
Qualify leads before running Zalo-based marketing in Vietnam.
No-code CSV REST API Exportable results
Signal 1
Vietnam reach check — confirm in bulk which numbers hold a registered Zalo account.
Signal 2
Cleaner local lists — keep only real Zalo users before launching Zalo Official Account or CRM campaigns.
Signal 3
Privacy-safe — a passive check that never messages, adds, or notifies the account holder.
Zalo FAQ
Can I check phone numbers against Zalo in bulk?
Yes. Upload a CSV of up to hundreds of thousands of numbers or call the REST API, then download one registered or not-registered result per number, billed only for successful checks.
Why check Zalo registration for a Vietnamese audience?
Zalo is used across everyday life in Vietnam — chat, payments, and even some government services run through it — so a Zalo-registered signal is a strong proxy for whether a Vietnamese contact is reachable through business messaging channels beyond SMS.
Does the check contact or notify the Zalo user?
No. The check is passive and only reads the registration signal. The Zalo account is never messaged, friend-requested, or notified.
Is there a free trial?
Yes. Contact our support team to claim 1,000 free checks for testing. After that every check is pay-as-you-go with no monthly fee, and the credits you top up never expire.