VK Number Checker API — Bulk Verification | NumberChecker

The VK Number Checker API accepts a text file of phone numbers, creates an asynchronous bulk task, and exports a result file. This repository contains a runnable integration in seven languages.

• Product page: https://numberchecker.ai/products/vk-checker
• API documentation: https://docs.numberchecker.ai/vk-checker
• API base URL: https://api.numberchecker.ai
• Authentication: X-API-Key
• Get an API key: https://platform.numberchecker.ai

Note

This repository covers the standalone product code vk only. Other product codes are outside its scope.

Product facts

API fact	Value
Product code	vk
Input	Text file, one phone per line
Processing mode	Asynchronous bulk task
Minimum batch	1,000 identifiers
Maximum batch	10,000,000 identifiers
Export fields	number, activated

Workflow

1. Submit the input file to POST /v1/tasks with task_type=vk.
2. Poll POST /v1/gettasks with the returned task_id.
3. When status=exported, download result_url.

export NUMBERCHECKER_API_KEY="YOUR_API_KEY"
curl -X POST 'https://api.numberchecker.ai/v1/tasks' \
  -H "X-API-Key: $NUMBERCHECKER_API_KEY" \
  -F 'file=@examples/numbers.txt' \
  -F 'task_type=vk'

Task states are pending, processing, exported, and failed. Download the result only after export and preserve the returned column names exactly. GET /v1/balance reads the current account balance.

Input and output

Provide one phone number per line in international E.164 format, including the country code. The exported fields are: number, activated.

Errors and safe integration

Typical responses include 400 invalid input, 401 invalid API key, 402 insufficient balance, 404 unknown task, 413 oversized upload, and 500 temporary server error. Retry transient 500 responses with capped backoff; correct the input or credentials before retrying other errors. Read keys from NUMBERCHECKER_API_KEY and never expose them in browser code or source control. Process only identifiers you are authorized to verify.

Runnable examples

Complete submit → poll → download clients are available in the server-side examples:

• examples/python
• examples/nodejs
• examples/go
• examples/java
• examples/csharp
• examples/php
• examples/shell

Run the server-side examples from the repository root using the exact commands listed in each language README; each command passes examples/numbers.txt. All server-side examples read NUMBERCHECKER_API_KEY from the environment and fail fast if it is missing.

FAQ

Is this a realtime single-identifier API?

No. It is an asynchronous bulk API for uploaded lists.

Which product does this repository support?

Only vk. The task type is intentionally fixed to that product code.

Where can I find current pricing?

See the NumberChecker pricing page. This repository does not hard-code a price.

Official resources

• Product: https://numberchecker.ai/products/vk-checker
• Documentation: https://docs.numberchecker.ai/vk-checker
• Dashboard and API keys: https://platform.numberchecker.ai
• Pricing: https://numberchecker.ai/pricing
• OpenAPI contract: openapi.yaml
• License: MIT

NumberChecker is not affiliated with the third-party service named by this product family. Use this API only for authorized processing and comply with applicable privacy laws and platform terms.

Last reviewed: 2026-08-18 · Maintained by NumberChecker.