Zalo Days Checker API: Bulk Phone Number Verification

Check Zalo account activity information for phone numbers in your file, including UID, last seen, and active days. Same batch task workflow as other social / messenger checkers.

Upload detection file — example:

curl --location 'https://api.checknumber.ai/v1/tasks' \
--header 'X-API-Key: API-KEY' \
--form 'file=@"./numbers.txt"' \
--form 'task_type="zalo_active"'

Check task status — example:

curl --location 'https://api.checknumber.ai/v1/gettasks' \
--header 'X-API-Key: API-KEY' \
--form 'task_id="task_id"'

Response after upload succeeds

{
    "task_id": "d4g8o46p2jvh04o9uolg",
    "status": "pending",
    "total": 2049,
    "message": "Task created successfully",
    "created_at": "2025-11-21T15:58:08.916446594Z"
}

Response while processing

{
    "created_at": "2025-11-21T08:27:09.933Z",
    "updated_at": "2025-11-21T08:27:10.241Z",
    "task_id": "d4g24nep2jvh04o9uoh0",
    "user_id": "wfi7wGPS4B4PdtTMox5Y",
    "status": "processing",
    "total": 2049,
    "success": 1024,
    "failure": 0
}

Response when finished (exported)

{
    "created_at": "2025-11-21T08:27:09.933Z",
    "updated_at": "2025-11-21T08:27:10.241Z",
    "task_id": "d4g24nep2jvh04o9uoh0",
    "user_id": "wfi7wGPS4B4PdtTMox5Y",
    "status": "exported",
    "total": 2049,
    "success": 2049,
    "failure": 0,
    "result_url": "https://example-link-to-results.zip"
}

Upload file request URL

POST https://api.checknumber.ai/v1/tasks

Upload file request parameters

Parameter	Description
file	file, one phone number per line (E.164 format)
task_type	string, set to zalo_active

Check task status request URL

POST https://api.checknumber.ai/v1/gettasks

Check task status request parameters

Parameter	Description
task_id	string, Task ID returned from task creation

Result fields

Field	Description
Number	Phone number in E.164 format
zalo	Whether the number is registered on Zalo (yes / no style; labels per export)
uid	Zalo user ID
lastseen	Last seen timestamp
activedays	Number of active days

Response format

Field	Description
created_at	Timestamp when task was created
updated_at	Timestamp of last task status update
task_id	Unique task identifier
user_id	User ID
status	pending · processing · exported
total	Total phone numbers processed
success	Numbers successfully identified
failure	Numbers that failed processing
result_url	Download URL when status is exported

Status codes

Status	Description
200	charge, request successful
400	free, bad request
500	free, server error