WA Lookup

Bulk product ws_active_batch

WhatsApp activity check · Bulk

Registration status plus last-active time, active days and the Business flag, so you can tell live numbers from dormant ones across a whole list.

Usage cost: $0.006 per checkResponse mode: Asynchronous task2,000–1,000,000 numbers per taskPOST /api/v1/bulk-tasks
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API contract

Two calls run a whole task

Submit to get a task id, then check the task by that id. When it succeeds the response carries the result file download link — there is no third endpoint.

1. Submit the file
curl -X POST "https://walookup.com/api/v1/bulk-tasks" \
  -H "X-API-Key: sk_your_api_key" \
  -F service_type=ws_active_batch \
  -F file=@numbers.txt
2. Check the task
curl "https://walookup.com/api/v1/bulk-tasks/123" -H "X-API-Key: sk_your_api_key"
Response
{
  "code": 0,
  "msg": "ok",
  "data": {
    "id": 123,
    "product": "ws_active_batch",
    "status": "success",
    "total": 2000,
    "success_cnt": 2000,
    "charged_amount_micros": 12000000,
    "result_url": "https://…/result.zip"
  }
}
Read the full API docs

Result fields

Columns in the result file

The download is a zip: alongside this full table it splits registered and unregistered numbers into separate lists.

ColumnExampleMeaning
number+14155552671The submitted phone number.
activatedyesWhether the number is registered on WhatsApp.
activetime2026-08-01 16:15:49The most recent activity time observed.
activedays33Days since that activity — smaller is more recent.
businessnoWhether this is a WhatsApp Business account.

How it runs

What happens to a bulk task

Bulk is not realtime made bigger — it is submit once, run in the background, collect later. You do not need to keep the page open; task state and results stay in your dashboard.

  1. Upload the fileA .txt or .csv with one number per line. It is streamed straight through; nothing is written to disk.
  2. Precheck and reserveFormat and single-country rules are checked first, then balance is reserved for the valid lines. Nothing is charged if the precheck fails.
  3. Run in the backgroundThe task runs on its own — close the page if you like. A failure is reported straight away and fully refunded.
  4. Download the resultCollect the file from the bulk check page. You pay only for numbers that actually returned a result; the difference is refunded.

Best for

When to reach for this one

  • Separating live from dormant numbers
  • Prioritising re-activation lists
  • Allocating campaign budget
  • Scoring list quality

WhatsApp bulk activity check returns last-active time, active days, and the business flag on top of registration status. Registered does not mean still in use — this product separates long-dormant numbers from the rest so budget goes to people who will actually see the message.

Clear boundaries

What this product does not do

  • It is not identity verification. A result describes the number's public state on the platform; it cannot confirm who owns the number.
  • It never returns message history, conversation content, or any private account content.
  • Choose the country your numbers belong to when submitting a task. The list should be essentially that one country — neighbours on the same dialling code do not count as cross-country, and more than 10% genuinely from other countries is rejected before any charge.
  • Results reflect the moment the task ran. Run it again for a fresh state — stored results are never refreshed for you.
  • Download links expire. Fetch the file soon after the task finishes; if a link expires, check the task again for a new one.

Product FAQ

About Activity check

Why is the minimum 2,000 numbers?

Below that, the realtime endpoints are cheaper and faster — one request returns the whole answer with no task scheduling. Bulk earns its keep on whole large lists.

What happens to invalid numbers in the file?

The precheck drops malformed lines and they never enter the billable count. Of the numbers that remain, any the upstream cannot resolve are not charged either — you pay only for numbers that actually return a result.

How long does a task take?

It depends on the number count and the product. You can close the page after submitting; the task runs in the background and the result waits for you on the bulk check page.

Do I get refunded if it fails?

Yes. A failed task is refunded in full. If the task succeeds but some numbers return nothing, that portion is refunded automatically. The gap between what was reserved and what was actually charged always comes back.

Choosing

Realtime check or bulk check

Realtime checkBulk check
How many numbers1 for a single check; up to 500 in the dashboard, up to 100 via the multi endpointFrom 2,000 up to 1,000,000
Getting resultsRight away: single and multi-endpoint answer in the same response; the dashboard returns them one by oneDownload a result file when the task finishes
Country / regionNo restriction — mix freely in one requestPick one country/region on submission; the list should be essentially that country, and too many numbers from elsewhere are rejected before any charge
Result shapeJSON, fields per numberResult file (zip with the full table and split lists)
Typical useForm validation, agent lookups, pre-send gatingList hygiene, pre-campaign filtering, stored-data cleanup

Realtime check · View pricing

Related products

Other bulk products

ws_batchWhatsApp registration check · BulkUpload a whole file of numbers, find out which ones are registered on WhatsApp, and download the result file when it finishes.ws_profile_batchWhatsApp profile check · BulkAvatar and avatar category, estimated age band, gender, skin tone, hair colour and a business flag across a whole list, for segmentation and audience work.

Create an account to submit a bulk task

Bulk and realtime checks draw on the same balance — nothing extra to enable. Sign up and upload your first file on the bulk check page.

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