> For the complete documentation index, see [llms.txt](https://docs.geeknums.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.geeknums.io/checknumber-api-phone-number-verification-service.md).

# CheckNumber API - Phone Number Verification Service

Welcome to **CheckNumber API** — a **phone number verification** and **validation service** for developers and businesses worldwide.

## API Introduction

CheckNumber provides **advanced phone number verification APIs** that help you validate and verify phone numbers across 20+ platforms in bulk. Whether you need to verify WhatsApp registrations, detect social media accounts, check cryptocurrency exchange users, or query phone carrier information, CheckNumber has you covered.

**Typical use cases:**

* Marketing list cleaning — remove inactive numbers before sending campaigns
* Fraud prevention — verify user-provided phone numbers on registration
* CRM enrichment — identify which platforms your contacts use
* Crypto exchange KYC — cross-check user phone numbers against exchange registrations

## Quick Start

{% stepper %}
{% step %}

### Get your API Key

Sign up at [checknumber.ai](https://checknumber.ai/) and retrieve your API key from the dashboard.
{% endstep %}

{% step %}

### Submit a batch task

Upload a `.txt` or `.csv` file with one phone number per line (E.164 format, e.g. `+8613800138000`):

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

{% endstep %}

{% step %}

### Poll for results

```bash
curl --location 'https://api.checknumber.ai/v1/gettasks' \--header 'X-API-Key: YOUR_API_KEY' \--form 'task_id="TASK_ID_FROM_STEP_2"'
```

When `status` becomes `exported`, download the result file from `result_url`.
{% endstep %}
{% endstepper %}

## API Overview

| Item           | Details                                |
| -------------- | -------------------------------------- |
| Base URL       | `https://api.checknumber.ai`           |
| Authentication | `X-API-Key` header                     |
| Submit task    | `POST /v1/tasks` (multipart/form-data) |
| Query status   | `POST /v1/gettasks` (form-data)        |
| Check balance  | `GET /v1/balance`                      |
| File format    | `.txt` or `.csv`, one entry per line   |
| Max batch size | 1,000,000 entries per task             |

### Authentication

All requests require your API key passed in the request header:

```
X-API-Key: YOUR_API_KEY
```

### Task Status

| Status       | Meaning                                   |
| ------------ | ----------------------------------------- |
| `pending`    | Task queued, waiting to start             |
| `processing` | Task is being processed                   |
| `exported`   | Results ready, download from `result_url` |

## Product Catalog

### Social Platform Registration Checkers

#### Telegram

| Product                                                                     | Task type   | Return fields                                                                                                                                              |
| --------------------------------------------------------------------------- | ----------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------- |
| [CheckNumber](broken://pages/309bf18ac21ed972ba3dd7cee5bcb33f7785bc25)      | `tg`        | `number`, `activated`                                                                                                                                      |
| [Activity Checker](broken://pages/dc4c5ba1d2a61122abc72118ccd8b53086795399) | `tg_active` | `number`, `activated`, `uid`, `username`, `lastseen`, `activedays`, `member`                                                                               |
| [Profile Checker](broken://pages/e1cf403b5743084031536b28aa79561e20e571af)  | `tg_avatar` | `Phone`, `activated`, `uid`, `username`, `Gender`, `Age`, `Ethnicity`, `Avatar`, `Last Online Time`, `Active Days`, `Is Member`, `first_name`, `last_name` |

#### WhatsApp

| Product                                                                     | Task type   | Return fields                                                                                      |
| --------------------------------------------------------------------------- | ----------- | -------------------------------------------------------------------------------------------------- |
| [CheckNumber](broken://pages/fa139c679768098c9485c3dda1cdb39f3f28679e)      | `ws`        | `number`, `activated`                                                                              |
| [Activity Checker](broken://pages/f6e70ddd3916e326631b8fd2df2f131f19a1e461) | `ws_active` | `number`, `activated`, `activetime`, `activedays`, `business`                                      |
| [Profile Checker](broken://pages/eb792ad936da2ea344ec71f3c79363c1c609bfa0)  | `ws_avatar` | `number`, `activated`, `age`, `avatar`, `category`, `gender`, `hair_color`, `number`, `skin_color` |

#### CheckNumber

| Product                                                                            | Task type          | Return fields             |
| ---------------------------------------------------------------------------------- | ------------------ | ------------------------- |
| [Validity Checker](broken://pages/d73f4fe7693d080b221de55430377432bbd2622a)        | `phoneCheck`       | `number`, `activated`     |
| [Activity Checker](broken://pages/0b517bdbcbb32e330a138ce2bd0b3c267132a258)        | `active_check`     | `number`, `activated`     |
| [High-Value Checker](/high-value-users-checker-api-bulk-phone-number-detection.md) | `high_value_users` | `Mobile Number`, `Result` |

#### Viber

| Product                                                                     | Task type      | Return fields                                                                                                                                       |
| --------------------------------------------------------------------------- | -------------- | --------------------------------------------------------------------------------------------------------------------------------------------------- |
| [CheckNumber](broken://pages/54fa0a68d15242b893bf9eb2fa4ce2622e982e9c)      | `viber`        | `number`, `activated`                                                                                                                               |
| [Activity Checker](broken://pages/80fa722b193d94f6d4f5accd747e725715e5069f) | `viber_active` | `number`, `activated`, `mid`, `last_online_time`, `active_days`                                                                                     |
| [Profile Checker](broken://pages/e1778418c9a04f5dee1efa1ead1565b64b3741f8)  | `viber_senior` | `number`, `activated`, `last_online_time`, `active_days`, `mid`, `nickname`, `person_count`, `avatar_type`, `age`, `skin_color`, `gender`, `avatar` |

#### iMessage

| Product                                                                | Task type  | Return fields         |
| ---------------------------------------------------------------------- | ---------- | --------------------- |
| [CheckNumber](broken://pages/1bfbd61a8d6790ce3e3c6c596710800433b2f63c) | `imessage` | `number`, `activated` |

#### RCS

| Product                                                                | Task type | Return fields                   |
| ---------------------------------------------------------------------- | --------- | ------------------------------- |
| [CheckNumber](broken://pages/4e2b6142fc546a3ea49cc24c5584b9fa038c6acc) | `rcs`     | `number`, `activated`, `system` |

#### Signal

| Product                                                                | Task type | Return fields         |
| ---------------------------------------------------------------------- | --------- | --------------------- |
| [CheckNumber](broken://pages/2bc60e2e14498ceba5cd0dd8a60e72f19b2c27b1) | `signal`  | `number`, `activated` |

#### VK

| Product                                                                | Task type | Return fields         |
| ---------------------------------------------------------------------- | --------- | --------------------- |
| [CheckNumber](broken://pages/11d9d10b8c108cb944fa5fdb9d53dc93ffe11761) | `vk`      | `number`, `activated` |

#### Apple ID

| Product                                                                   | Task type     | Return fields         |
| ------------------------------------------------------------------------- | ------------- | --------------------- |
| [CheckNumber](/apple-bulk-number-checker-api-fast-number-verification.md) | `apple`       | `number`, `activated` |
| [Email Checker](/apple-email-checker-api-fast-email-verification.md)      | `apple_email` | `email`, `activated`  |

#### Facebook

| Product                                                                      | Task type        | Return fields         |
| ---------------------------------------------------------------------------- | ---------------- | --------------------- |
| [CheckNumber](/facebook-bulk-number-checker-api-fast-number-verification.md) | `facebook`       | `number`, `activated` |
| [Email Checker](/facebook-email-checker-api-fast-email-verification.md)      | `facebook_email` | `email`, `activated`  |

#### Amazon

| Product                                                                    | Task type      | Return fields         |
| -------------------------------------------------------------------------- | -------------- | --------------------- |
| [CheckNumber](/amazon-bulk-number-checker-api-fast-number-verification.md) | `amazon`       | `number`, `activated` |
| [Email Checker](/amazon-email-checker-api-fast-email-verification.md)      | `amazon_email` | `email`, `activated`  |

#### Instagram

| Product                                                                  | Task type         | Return fields         |
| ------------------------------------------------------------------------ | ----------------- | --------------------- |
| [CheckNumber](broken://pages/17d98d3f9c645c3294b403c5e331ad8ce6ed17c3)   | `instagram`       | `number`, `activated` |
| [Email Checker](broken://pages/e5f2c63e442e323a44bf9d730e7d487d7aa202f0) | `instagram_email` | `email`, `activated`  |

#### MAX

| Product                                                                    | Task type  | Return fields         |
| -------------------------------------------------------------------------- | ---------- | --------------------- |
| [CheckNumber](broken://pages/b9d0fab897a2a2c78962273566a8afc5b25b66fa)     | `max`      | `number`, `activated` |
| [Profile Checker](broken://pages/d952e4ddf2a0d314d802d6f3f7c80457d6877875) | `max_full` | `number`, `activated` |

#### Netflix

| Product                                                                  | Task type       | Return fields         |
| ------------------------------------------------------------------------ | --------------- | --------------------- |
| [CheckNumber](broken://pages/db93e71dcd932a87dc610a622c61e6d27565a80f)   | `netflix`       | `number`, `activated` |
| [Email Checker](broken://pages/700ed0c0006f3df296f7a648c1776fe4d3df8ab1) | `netflix_email` | `email`, `activated`  |

#### Line

| Product                                                                    | Task type     | Return fields         |
| -------------------------------------------------------------------------- | ------------- | --------------------- |
| [CheckNumber](broken://pages/203ca7c81784169b47d48caa22cfb03fb1e4cafb)     | `line`        | `number`, `activated` |
| [Profile Checker](broken://pages/df83dd05687b9c7059a674f16e76b6636fcf3632) | `line_senior` | `number`, `activated` |

#### X (Twitter)

| Product                                                                  | Task type       | Return fields         |
| ------------------------------------------------------------------------ | --------------- | --------------------- |
| [CheckNumber](broken://pages/6ce28b105f1f92ee8f8b95695c01427619b32d57)   | `twitter`       | `number`, `activated` |
| [Email Checker](broken://pages/e6753551aa0171fc890b89b5c3f09f865b44fe48) | `twitter_email` | `email`, `activated`  |

#### Telegram (username)

| Product                                                                         | Task type              | Return fields                                                                                                                             |
| ------------------------------------------------------------------------------- | ---------------------- | ----------------------------------------------------------------------------------------------------------------------------------------- |
| [Registration Checker](broken://pages/985942ceacbfca243a167f9ba99dbc937fdc79b4) | `tg_username`          | `username`, `activated`, `avatar_url`                                                                                                     |
| [Activity Checker](broken://pages/d87490680993309b5de80435fcbadad2bd75d7d3)     | `tg_username_activity` | `username`, `activated`, `uid`, `lastseen`, `activedays`, `member`, `avatar_url`                                                          |
| [Profile Checker](broken://pages/383c58da8b686f92dce72386e1023b486af16925)      | `tg_username_profile`  | `username`, `activated`, `avatar_url`, `uid`, `lastseen`, `activedays`, `member`, `category`, `gender`, `hair_color`, `skin_color`, `age` |

#### LinkedIn

| Product                                                                          | Task type          | Return fields                                                                         |
| -------------------------------------------------------------------------------- | ------------------ | ------------------------------------------------------------------------------------- |
| [CheckNumber](broken://pages/7fc6efd1df0246c133192d035d3b7b8b1bdb625f)           | `linkedin_phone`   | `number`, `activated`                                                                 |
| [Email Checker](broken://pages/c973be1794bb22349da6d5b15f37d463878a65cd)         | `linkedin`         | `email`, `activated`                                                                  |
| [Email Profile Checker](broken://pages/34c07a96c587caab4ccb8ef3683adb0785ecbb3c) | `linkedin_profile` | `email`, `activated`, `country`, `gender`, `industry`, `job_title`, `inferred_salary` |

#### Zalo

| Product                                                                | Task type | Return fields         |
| ---------------------------------------------------------------------- | --------- | --------------------- |
| [CheckNumber](broken://pages/71d178b5f7d20f9e18e61f7af0df43f7b624e36e) | `zalo`    | `number`, `activated` |

#### TikTok

| Product                                                                | Task type | Return fields                            |
| ---------------------------------------------------------------------- | --------- | ---------------------------------------- |
| [CheckNumber](broken://pages/a6ae3329d76dc3305514cbffc9270e0ca347231f) | `tiktok`  | `number`, `activated`, `username`, `uid` |

#### Microsoft

| Product                                                                | Task type   | Return fields         |
| ---------------------------------------------------------------------- | ----------- | --------------------- |
| [CheckNumber](broken://pages/46138aa1515f1da14464e6fcaadadddf7db079de) | `microsoft` | `number`, `activated` |

#### Snapchat

| Product                                                                | Task type  | Return fields         |
| ---------------------------------------------------------------------- | ---------- | --------------------- |
| [CheckNumber](broken://pages/714c6654542b4d36c31650d806bc93afbd18ad37) | `snapchat` | `number`, `activated` |

#### Messenger

| Product                                                                | Task type   | Return fields         |
| ---------------------------------------------------------------------- | ----------- | --------------------- |
| [CheckNumber](broken://pages/e609e579c4cbdb61c62d5bbe9d4afacdf2517fc2) | `messenger` | `number`, `activated` |

#### GoTo

| Product                                                            | Task type | Return fields         |
| ------------------------------------------------------------------ | --------- | --------------------- |
| [CheckNumber](/goto-checker-api-bulk-phone-number-verification.md) | `goto`    | `number`, `activated` |

#### Threads

| Product                                                                | Task type | Return fields         |
| ---------------------------------------------------------------------- | --------- | --------------------- |
| [CheckNumber](broken://pages/ed666996326397aeff9832207f8514af7fe05e36) | `threads` | `number`, `activated` |

#### Spotify

| Product                                                                  | Task type       | Return fields        |
| ------------------------------------------------------------------------ | --------------- | -------------------- |
| [Email Checker](broken://pages/abae294036e3bac5aa916787756ff47b4d1fe6ab) | `spotify_email` | `email`, `activated` |

#### Band

| Product                                                            | Task type | Return fields         |
| ------------------------------------------------------------------ | --------- | --------------------- |
| [CheckNumber](/band-checker-api-bulk-phone-number-verification.md) | `band`    | `number`, `activated` |

#### DHL

| Product                                                                   | Task type | Return fields         |
| ------------------------------------------------------------------------- | --------- | --------------------- |
| [CheckNumber](/dhl-checknumber-api-bulk-delivery-account-verification.md) | `dhl`     | `number`, `activated` |

#### Sideline

| Product                                                                | Task type  | Return fields         |
| ---------------------------------------------------------------------- | ---------- | --------------------- |
| [CheckNumber](broken://pages/2adcd8c2127b9b27cd88909eb8b774e32eca7c05) | `sideline` | `Number`, `activated` |

#### Airbnb

| Product                                                                        | Task type | Return fields         |
| ------------------------------------------------------------------------------ | --------- | --------------------- |
| [CheckNumber](/airbnb-checker-api-bulk-phone-number-registration-detection.md) | `airbnb`  | `number`, `activated` |

#### Pornhub

| Product                                                                  | Task type | Return fields        |
| ------------------------------------------------------------------------ | --------- | -------------------- |
| [Email Checker](broken://pages/f0f8dc968b0b7d2beab83e5c160189b10583b1d1) | `pornhub` | `email`, `activated` |

#### Temu

| Product                                                                | Task type | Return fields         |
| ---------------------------------------------------------------------- | --------- | --------------------- |
| [CheckNumber](broken://pages/7657ede0f091d9d86b3c43a85311a472855a7d13) | `temu`    | `number`, `activated` |

#### Botim

| Product                                                          | Task type      | Return fields                          |
| ---------------------------------------------------------------- | -------------- | -------------------------------------- |
| [CheckNumber](/botim-checknumber-api-bulk-registration-check.md) | `botim`        | `number`, `activated`                  |
| [Age & Gender Checker](/botim-age-and-gender-checker-api.md)     | `botim_gender` | `number`, `activated`, `gender`, `age` |

### Exchange Registration Checkers

#### Binance

| Product                                                                     | Task type       | Return fields         |
| --------------------------------------------------------------------------- | --------------- | --------------------- |
| [CheckNumber](/binance-bulk-number-checker-api-fast-number-verification.md) | `Binance`       | `number`, `activated` |
| [Email Checker](/binance-email-checker-api-bulk-email-verification.md)      | `binance_email` | `email`, `activated`  |

#### KuCoin

| Product                                                                  | Task type      | Return fields         |
| ------------------------------------------------------------------------ | -------------- | --------------------- |
| [CheckNumber](broken://pages/c7aa8dccfd888d424d9e4227f23407f233985497)   | `Kucoin`       | `number`, `activated` |
| [Email Checker](broken://pages/659315b9b624a28c6297ebd00ee364ea62a0a619) | `kucoin_email` | `email`, `activated`  |

#### Htx

| Product                                                                       | Task type   | Return fields         |
| ----------------------------------------------------------------------------- | ----------- | --------------------- |
| [CheckNumber](/htx-bulk-number-checker-api-fast-phone-number-verification.md) | `htx`       | `number`, `activated` |
| [Email Checker](broken://pages/7dc55b3c9c79207652b44a0b0702cc77e1ea5368)      | `htx_email` | `email`, `activated`  |

#### CoinW

| Product                                                                   | Task type     | Return fields         |
| ------------------------------------------------------------------------- | ------------- | --------------------- |
| [CheckNumber](/coinw-bulk-number-checker-api-fast-number-verification.md) | `coinW`       | `number`, `activated` |
| [Email Checker](/coinw-email-checker-api-bulk-email-verification.md)      | `coinw_email` | `email`, `activated`  |

#### Crypto.com

| Product                                                                       | Task type      | Return fields        |
| ----------------------------------------------------------------------------- | -------------- | -------------------- |
| [Email Checker](/crypto.com-email-checker-api-bulk-registration-detection.md) | `crypto_email` | `email`, `activated` |

#### OKX

| Product                                                                | Task type | Return fields         |
| ---------------------------------------------------------------------- | --------- | --------------------- |
| [CheckNumber](broken://pages/9cb210e376b5401707eb19dd63d6ff308648f53a) | `okx`     | `number`, `activated` |

### Email And Global Carrier Checkers

#### Email Validation

| Product                                                                | Task type     | Return fields        |
| ---------------------------------------------------------------------- | ------------- | -------------------- |
| [Upload Task](/bulk-email-checker-api-gmail-outlook-yahoo-and-more.md) | `email_check` | `email`, `activated` |

#### Global Carrier Checker

| Product                                                                           | Task type    | Return fields                                                                              |
| --------------------------------------------------------------------------------- | ------------ | ------------------------------------------------------------------------------------------ |
| [Global Carrier Checker](broken://pages/4004e9ab67b0d38c13abb2b2808420257eb1fc9e) | `usaCarrier` | `number`, `number_type`, `country_code`, `carrier`, `underlying_carrier`, `region`, `city` |

#### Advanced US Carrier Checker

| Product                                                                        | Task type            | Return fields                              |
| ------------------------------------------------------------------------------ | -------------------- | ------------------------------------------ |
| [Advanced US Carrier Checker](/advanced-us-carrier-api-bulk-carrier-lookup.md) | `us_carrier_premium` | `Number`, `number_type`, `carrier`, `city` |

## Shared utilities

| API                                                              | Description                                                                          |
| ---------------------------------------------------------------- | ------------------------------------------------------------------------------------ |
| [Global Phone Carrier Inquiry](/global-phone-carrier-inquiry.md) | Legacy synchronous single-number carrier lookup; not part of the 74-product catalog. |
| [Balance Query API](/balance-query-api-check-account-balance.md) | Query available account balance.                                                     |


---

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Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:

```
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```

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